 Raise the Rev limit?
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Loquacious
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Loquacious
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Has anbody seen this?I know there are some differences between bonnes and our bikes, but maybe someone here with a better understanding can chime in?
Stewart
.......
"It's outside your field of expertise."
"Poppycock normally is."
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Re: Raise the Rev limit?
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Oil Expert
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Oil Expert
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Very interesting. There was a guy in Sweden doing this a while back, name of Jan something I think, but you had to send him your computer and he'd mod it and send it back. Obviously you couldn't use a bonneville computer in our bikes coz the bonne's coils both fire at once, whereas ours are 90 degrees apart. No reason they couldn't do the same mod on ours tho. If you're on an America you can already get a 500rpm higher redline by getting your hands on a speedmaster computer, so theoretically you could get a 1500rpm higher redline by putting a mod'd speedy computer in an america. Would it be safe in the long term? Probably not, or Triumph would have set it higher themselves.
The website mentioned in the auction looks like it's still being built. If you click on one of the "bike type" pics you just get the pic instead of a menu. Worth keeping an eye on though.
Matt
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Re: Raise the Rev limit?
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3/4 Throttle
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"jojje" in Sweden does this box modifying - except for Americans.
Let me caution people here: these new Triumph twins come with cast pistons and steel con rods! The old 650's had forged pistons and forged aluminum con rods, so they could take the high rpms.
Revving the snot out of a cast piston engine is just asking for trouble, as in "It got blowed up!"
But, if one installs a Wiseco big bore kit, one gets replacement forged pistons, which are certainly strong enough to survive high rpm blasts.
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Re: Raise the Rev limit?
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Loquacious
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i would rather have a few less rpm and be able to bonce off the rev limiterwhenever i want or should i say when i do by accident and not worrie about the bike
Frank
(Former)05 BA tbike pipes, ai removed, Freak, mikuni hsr 42's, 904, ported/polished head, 1mm oversized valves
NOW-2010 silver and black tbird
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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Quote:
"jojje" in Sweden does this box modifying - except for Americans.
Let me caution people here: these new Triumph twins come with cast pistons and steel con rods! The old 650's had forged pistons and forged aluminum con rods, so they could take the high rpms.
Revving the snot out of a cast piston engine is just asking for trouble, as in "It got blowed up!"
But, if one installs a Wiseco big bore kit, one gets replacement forged pistons, which are certainly strong enough to survive high rpm blasts.
Hmmm......that sounds worrisome looking at it from this perspective....if 1000 more RPM's would make the top end unreliable in what would be a catistrophic failure, then 1000 RPMS less (stock limiter) doesn't make me feel too reassured about my stock engine. In other words, how reliable is the stock setup if increasing the rev limit by 1k risks catistrophic failure !?
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Re: Raise the Rev limit?
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Loquacious
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1000 rpm is actually a lot in a motor. at stock rev limiter i would not have any worries about anything. it is proven that these motors will last and take a beating without any problems. there are always a few with problems but as a whole these motors are very reliable. i read in a past post someone knowledgable with motorcycles saying triumh is right with BMW in reliability. and there are many members with 30+ thousand miles and not a problem at all.
Frank
(Former)05 BA tbike pipes, ai removed, Freak, mikuni hsr 42's, 904, ported/polished head, 1mm oversized valves
NOW-2010 silver and black tbird
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Re: Raise the Rev limit?
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Joined: May 2005
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Adjunct
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Adjunct
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Yeah, that just sounds like it's begging for problems. Talk about voiding the warranty! Jeez! And we thought the big-bore kit was bad! Eek!
Still, if someone's willing to guinea pig their bike... heh. Not me!
--Jaeger
NEUTIQUAM ERRO
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Re: Raise the Rev limit?
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Complete Newb
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Complete Newb
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I have received a Beta version of a CDI unit from www.procomengineering.com w/the rev limiter set at 8000 rpm. They will be selling for $129.95 when released. I am not worried about reliability since the Speed Master already has the limiter set at 8,000 rpm. However, the Triumph Manual shows the Igniter, which I assume is the same component, under the seat. Mine is not there. Does anyone know where it is actually located? I will post my results soon after I install it. Thanks, Doug
Skin Side Up - Rubber Side Down!
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Re: Raise the Rev limit?
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Old Hand
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There is much more to worry about than the durability of the rods and pistons. The torque and power curves suggest there is more power to be had beyond the redline. So, one must wonder why Triumph didn't set it higher. One consideration would be valve float. There is a limit to how strong the valve springs can be when the cams are running directly on the aluminum head and caps. If you want to make serious increases in the rev limit, you would also need to line bore the heads and cam caps, and install some substantial bearings.
Another consideration these days is noise. The faster you run an angine, the more noise it makes. This is such a touchy subject that the Lycoming O320 installed in an airplane I once flew had an orange patch on the tach. You could run the engine above or below the orange patch, but it was illegal to hold it in that zone because the exhaust system and prop resonated there, making excessive noise.
Other things to consider are the cam drive chain and tensioner design, all that somewhat delicate looking machinery in the primary case, the effects of turning the balance shafts faster, etc.
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python
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Re: Raise the Rev limit?
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Loquacious
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Our bikes will not take an increase in the rev limiter like the standard Bonnevilles. While the America could get a slight benefit from a Speedmaster CDI because the limiter in an America kicks in at 7400 rpm and the Speedmaster's is 7900 rpm, the cost of an OEM replacement wouldn't make it worth the money. Jojje, the Swede who can change the rev limiter on Bonnies, had this to say at Trat.net; "And replacing the TPS with a new one won't cure the cutting out problem, I'm 100% sure there is nothing wrong with your TPS, the all cut out soner or later, removing the TPS might move the cut out rpm higher than the stock limiter but even without the TPS a 270 deg engine will cut out at anything above 8100rpm". Now although that statement had to do with a topic about removing the TPS, I recall in other posts of his that the 270 degree motors do not benefit from raising the rev limiter, because they'll cut out at 8100 rpm no matter what you do. In another post he said much the same thing; "Removing the TPS will give you the lowest advance at all revs. The TPS function is to give you more advance at low load (part throttle) It does nothing at idle or at full throttle. Don't know how this could fix the SM cut out problem though. I know that even without a TPS I could not get a SM to rev more than 8100 (modded program) before cutting out. A 360 Bonnie will rev 14000 if you are brave (only tried 11000 myself)" Again, the post is focused on the TPS, but also mentions that the Speedmaster(270 degree crank), won't go past 8100 rpms. If you want to ask him why that is, go here to his forum and ask. FWIW, I've been reading the boards about these new Triumph vertical twins for 2 1/2 years now. IMO Jojje knows more about these engines than anybody else around outside the Triumph factory. The AMA National Flat Track bike that Bill Gates built, and is the only new Triumph on the circuit, had it's rev limiter upped by Jojje.
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Re: Raise the Rev limit?
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3/4 Throttle
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What is needed for the Speedy and America ignitions is not so much a higher rev limiter, but a more powerful spark at all rpms.
A company that makes h.p. ignition boxes, such as Autotronics/MSD, should be able to do this easily. I fear, though, that the market is not nearly large enough to warrant building a product at a reasonable end-user cost.
A fellow could try his own custom ign. by using two independent boxes and triggering systems. The tricky part here is installing a second pick-up coil to trigger the second cylinder's box. (I would use two independent coils, too.)
The only problem, besides cost, is: what all does the stock ign. box control, and can some of these controls be left out of a custom system? On a race bike, there would be no problem, but a street bike would be a "horse of a different color".
p.s. Great post, SalMaglie!
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Re: Raise the Rev limit?
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Joined: Jan 2005
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Learned Hand
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Learned Hand
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The newer service manuel states that the rev limit is set at 7400 for both ba's and speedmaster's. My speedmaster which is an 03 is set at 7400 if the tach's correct. There may be some set at 7900 but not all. The tps issue which I also have is a different thing. Mine is currently unplugged. In my conversations with jojje in the past he believe the reason a 270 degree motor would not rev past 8100 was due to the close fireing postion of the crank. And that a completely new pick up system would be needed to do so.
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Re: Raise the Rev limit?
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Old Hand
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Quote:
Now although that statement had to do with a topic about removing the TPS, I recall in other posts of his that the 270 degree motors do not benefit from raising the rev limiter, because they'll cut out at 8100 rpm no matter what you do.
So, if I read this correctly, even with no limiter, the engine won't turn over 8100? And, that is because the engine cuts off as if it had a rev limiter? And, the 360 degree engine doesn't?
OK, looking at the differences, the America/SM 800 engines have a little milder exhaust cam timing and the different crank. The crank causes some differences in the ignition operation. The only way they would be able to sort out the ignition timing accurately enough is to have 2 crank position indicator lugs on the alternator rotor. Cranking speed variations would prevent sorting out which indicator is which, so the coils are undoubtedly fired twice per revolution while the 360 engine fires once per revolution. This reduces the effective dwell angle, especially on the leading cylinder. So, you'd have to use a very different coil design or re-engineer the entire ignition system to get as good a spark on the 270 degree engine.
Another possible factor is that the off spark on the 360 engine occures at the top of the exhaust stroke while, on the 270 engine, one occures in the middle of the exhaust stroke and, on the other cylinder, the middle of the intake stroke. That might not be such a big deal with 2 carburettors, but I know for certain it can cause a V-twin to pook out the carb when the mixure is just right.
As for mucking about with the TPS, that is only used to estimate the load on the engine and adjust the advance curve. For example, if the engine is holding at 4500 and the throttle is wide open, it is a safe bet that it is under a tremenduous load and the ignition should be retarded a bit. Think of this as the vacuum advance on older car engines.
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python
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Re: Raise the Rev limit?
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Loquacious
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Loquacious
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Like I said, you can ask Jojje here. He's the expert. I believe though that on the AMA flat track bike, he has raised the rev limit and that bike has a 270 degree crank in it. Maybe it can be done, but that bike is definitely not even close to stock.
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Re: Raise the Rev limit?
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Learned Hand
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As for mucking about with the TPS, that is only used to estimate the load on the engine and adjust the advance curve. For example, if the engine is holding at 4500 and the throttle is wide open, it is a safe bet that it is under a tremenduous load and the ignition should be retarded a bit. Think of this as the vacuum advance on older car engines.
The reason I was mucking with the tps, was that it wasnt operating correctly. Mine would completely shut the engine off at unpredictable times. Unplugging the tps solved this problem.
On the other note. I remember reading, I think it may have been the thunder pipe guys. They had a custom power comander for the 270 degree engine, and they do experienced the same problems with trying to go past 8100. I believe they said the power comander would get confused with the signal coming to fast with this pick up system. All that being said since our engines don't make additional hp past this point theres not a lot of advantage in going past it anyway. Just seems like 8000 would be a nice round number to set the limit. Giving you the possibility to gain a few more mph in say third and fourth. Course if you're just lazing around town all this is moot anyway. A nice speed triple would probably make more since in the quest for speed.
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Re: Raise the Rev limit?
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Anonymous
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Anonymous
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This topic of increasing the rev limiter range has come up mant times. Using the attached link, and if I am looking at it correctly, it appears that unless significant (translated $$$$$) modifications are made, the torque and HP begin to drop prior to max RPM. That said, what are the benefits to spooling up the engine to a point above where the meat resides? http://www.bonnevilleperformance.com/BAMM%20DYNO%20CHART.htmAlso, saw this one on ebay. http://cgi.ebay.ca/Triumph-Speedmaster-2...6QQcmdZViewItemNote the description; Vehicle Description 2003 Triumph Speedmaster This Triumph has been a garage queen of mine for two years. It is a mechanically sound and well maintained machine with many aftermarket goodies. The bike has 2332 miles total, has never been down, and is flawless from tip to tale. Regular and seasonal maintenance has always been performed. I am the original owner of this bike. It is a lot of fun to be on and rides easily only weighing somewhere in the 550 range. The bike was dyno tuned after all the mods and put 69 horsepower to the rear wheel. I don't ride it much and have decided to put it up for sale in the anticipation of a new ducati. Pictures don't do the bike justice, it is a fine example of a modern british cruiser. I've around $16,000 total in this Triumph, reserve is less than half that. The following parts came from www.bonnevilleperformance, www.performancemachine.com, www.barnettclutches.com, or my garage. 790 cc. engine: Stock 38mm carbs were replaced with a stage 2 kit from bonneville performance...Custom Carb setup: Twin mikuni 42mm carbs with custom intake manifolds,K & N air filters, air injection eliminated, and Sceptre shorty pipes. Oil cooler switched from radiator style to dual turbulated coolers. DYNO TUNED AT KINETIC PLAYGROUND IN TULSA RESULTING IN 69 RWHP, AROUND 79 AT THE CRANK ALL AT 5800 RPM (ADVERTISED STOCK CRANK POWER WAS SOMETHING LIKE 54 AT THE CRANK). The engine runs strong and breaths well; it is just now broken in. Joker bar risers, performance machine controls (wired internally through the bars), Barnett clutch and throttle cables, powder coated triple tree, fork lowered 3/4-inch, custom front blinker bracket, Kurakyn led turn signals front and back, Cowhide seat. Custom paint -Sherwin Williams Alkylyd Enamel black with an offset cream white stripe, hand rubbed by yours truly (I used to finish cars for a living) The bike is in Tulsa, Oklahoma and can be inspected prior to bidding/ purchase. I would prefer a local pickup but will assist in shipping at your expense. Upon auction completion I require $1500 security deposit within 72 hours; the balance to be paid at the time of pickup no later than 10 days total after the auction has ended. I also have all parts removed from the bike since stock up for grabs and will include for 500 beyond the closing price.
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Re: Raise the Rev limit?
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Joined: Jan 2005
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Worn Saddle
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Worn Saddle
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Sal,
The flat track bike Bill Gately runs has a custom made ignition system of some sort configured by jojje. He will not devulge any details though per his agreement with BG. Top secret. The bike is reported to spin in the 10k range and have so much power the biggest issue they faced was keeping the rear wheel attached to the ground.
A word to the wise is not necessary. It is the stupid ones who need the advice.
Pat
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Re: Raise the Rev limit?
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3/4 Throttle
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3/4 Throttle
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Speedy/America Go-fast Project: Get a 360* Bonny engine, big bore kit it, cam it, port and big intake valve the head, install an MSD motorcycle ign. box w/aftermarket coils, big carb it - and hang on!
Sounds like something our friend in Detroit, RaceDweeb could tackle.
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Re: Raise the Rev limit?
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Joined: Jan 2005
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Should be Riding
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Should be Riding
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Papa, I had that same thought reading this thread!! Find a wrecked bonnie for cheap, yank the motor and wiring for it, and go nuts!! Heck, you could even keep riding your BA/Speedie till it's done! Very sweet.
Benny
Black & Silver '02
Too many mods to list
Not enough miles ridden
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Re: Raise the Rev limit?
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Joined: Jan 2005
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Old Hand
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Old Hand
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If the resistance was really off on your TPS, it might have been causing the igniter to select an advance curve that didn't exist. I don't like the idea that the make you buy a new carb to replace it. It might be interesting to work out the resistance range on the TPS and replace it with a variable resistance mounted through the clock setter hole on the dash. There might be some times when manual advance curve selection would be useful.
As for making the engine run faster, first step would be to redo the ignition system. A different coil design or a mod to allow independant timing on each cylinder would be needed. This might be possible with 2 T100 igniters fired by 2 crank position sensors. Of course, the trigger tabs on the alternator rotor would have to be modified. Either a single tab like the 360 engine with the second sensor mounted 90 degrees around the rotor or the sensors side by side and the tabs modified to trip only the correct sensor.
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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Quote:
Don't know how this could fix the SM cut out problem though. I know that even without a TPS I could not get a SM to rev more than 8100 (modded program) before cutting out. A 360 Bonnie will rev 14000 if you are brave (only tried 11000 myself)"
But what about the notion that cast pistons and rods can't handle much more than the limiter allows? bAre bon nies equipped with forged parts, and if not why didn't 11k kill it?
And as for the notion they don't develop more power beyond the limiter, i'm sure mine would. It hits the limiter at a point where it feels like it's just starting to take off ! I think w/o the limiter the bike's accelleration time would go way down. But after hearing the cast vs forged argument i wouldn't try it even if i vould get my hands on a box. Not to mention the valve float someone else cited. But i bet this bike would be far better with a forged BB kit and stronger springs or whatever had to be done there to aliviate float. All i know is i can feel the bike beginning to build power pretty quickly at the point just before the limiter kicks in. My bike is piped and intake modded and hits the limiter fast and easy.
man, i wish they would just throw all this tuning BS out the window and build a uninhibited twin in the 1200cc reigon. No limiter, cast pistons and rods and a strong valve and cam setup and build it so it's "pipe and intake mod ready" if you will. Build it so it can be brought to a highly tuned stae easily w/o all the impossible to bypass BS. I mean, back in the day you could buy a honda 450 that was reliable, quiet, and would beat or at worse equal today's triumph 790 and 865 cruisers ! Even one of the guiys at RAT who has both a new twin (think it was a speedy tho can't recall for sure)and a 70's honda 450 told me his 450 was slightly quicker. And i asked him that because i recall having ridden them back then that if memory served, they seemed faster than my bike, and he agreed. Plus his bike has around 100k miles ! I just don't understand why triumph can't build a street legal 790/865 that could blast todays offerings and still be reliable and legal as noise goes. And by the way, wasn't the 450's redline at least 1k more than our bikes if not 2k? I love my bike dearly but i do wish it would perform as well as it should for it's size. (waiting impatiently to see what comes out of hinkley next)
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Re: Raise the Rev limit?
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Joined: Jan 2005
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Old Hand
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Old Hand
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Most "western world" engines are designed with a considerable safety factor as far as redlines go. You could probably go 50% above the rev limit before running into serious trouble. I'm pretty sure that coil saturation problems are the real reason that the 270 degree engine can't run as fast as the 360 degree one. I'm pretty sure that the 650 I once had was a good bit faster than my America. But, the bike weighed a lot less and so did I. If you could shave an America or S/M down to about 300 lb and put a skinny 16 year old on it, I'm sure it would be a whole different animal. 
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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Quote:
I'm pretty sure that the 650 I once had was a good bit faster than my America. But, the bike weighed a lot less and so did I. If you could shave an America or S/M down to about 300 lb and put a skinny 16 year old on it, I'm sure it would be a whole different animal.
Well, yea....but we're talking almost half the cc's between honda 450 and my speedy ! It may weel weigh a good deal more, but i don't even at my age and a 865 should be a lot faster than a 450. So much so that adding a passenger to the 865 should still leave it a good bit quicker. Half the cc's man !
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Re: Raise the Rev limit?
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Big Bore
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Big Bore
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Quote:
I mean, back in the day you could buy a honda 450 that was reliable, quiet, and would beat or at worse equal today's triumph 790 and 865 cruisers
What honda 450 are you talking about?
Just for grins, I looked up the specs on a '72 CB 450 four stroke
http://www.bikez.com/motorcycles/honda_cb_450_disc_1972.php
(couldn't find the torque)
Here's a couple of pertinent items:
HP - 45 HP @ 9000 rpm
Weight - 449.7 pounds
HP - 55 HP @ 6500 rpm
Weight - 504.9 pounds
I seriously doubt the above statement. Are you basing it on the perceptions of the RAT guy? I would want to see a real world test.
Quote:
Even one of the guys at RAT who has both a new twin (think it was a speedy tho can't recall for sure)and a 70's honda 450 told me his 450 was slightly quicker
Any mods on the 450 or the SM?
More information is definitely needed.....
"Never underestimate the power of human stupidity" - Robert Heinlein
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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As for mods i don't know, but he PM'd me and gave me and gave me a good deal of talk about his 2 bikes. I think he'd have mentionen any mods because he didn't seem biased either way. He said they were close but the 450 was a bit quicker. Granted it was many years ago i rode one but if memory serves he probably wasn't far off. And specs don't tell the whole story. I've owned bikes that were quicker or slower than thier ratings would suggest. The 450 has a higher redline and compression ratio too. I of course can't tell you i knw it's quicker, but i do recall it well enough to at least say there's not a big difference. And while lighter, again it's about 1/2 the size. I think that should say a lot right there. The cruisers, or at least mine, is w/o a doubt detuned considerably compared to what i know it would be capable of if not. I think my old yamaha 350 would have taken it with total ease in a 0-60 dual. granted it was a 2 stroke, but it was also a 350. Double the size and it would still be handicapped by 165 cc.
Last edited by iknowjohnny; 11/17/2005 3:59 PM.
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Re: Raise the Rev limit?
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Big Bore
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Big Bore
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Had a 70/72 (can't remember anymore) Yamaha 350 RD. Had bored it out twice. I could beat up to 750s in my sleep, every day, and all day. From a 350cc bike.
I would imagine that bike would eat any of today's SMs/BAs for lunch also, even Pat's.
But does that compare? I doubt it and after my above statement, I will retract my doubt from my previous post, OK? Perhaps that 450 could beat today's SMs/BAs.
So what does that say? My old 350 or your old 450 were better bikes?
I would laugh long and hard if the answer was yes.....
I'll take my Raven over ANY of those old bikes I used to have.
"Never underestimate the power of human stupidity" - Robert Heinlein
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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Ok, found an old post of his. Apparently the 450 IS modded...a one tooth larger sprocket ! So if anything it shouldn't be as quick as stock. His other bike is a bonnie too which should be quicker than mine from all i've read. Quote:
my CL 450 is stock except for a 16-t sprocket instead of the stock 15-T (I had to screw around with something...the final drive ratio is pretty silmilar to our Std Bonnies with an 18-t since the stock rear sprocket of the Honda is a 35-t). Please note though that the CL 450 red-lines at 9500 RPM at approx. 45 bhp, which gives it an extra 2000 RPM on top of the Bonnie's and it also weighs about 80 lbs less dry.
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Re: Raise the Rev limit?
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Learned Hand
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Learned Hand
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Quote:
So what does that say? My old 350 or your old 450 were better bikes?
No ! And that tells me you may be thinking i'm dissing the bike. I'm just saying i think they detuned them too much. Do i like my bike? The word "like" isn't quite strong enough....i friggin love it ! If i didn't i would buy a quicker bike and be done with it. But just as i wouldn't divorce a woman who i married because she's perfect in all respects except she had small cans, i have no intention of divorcing my bike. I love the triumph cruisers. The speedmaster is my absolute dream bike in 95% of ways. But like ANY bike they aren't perfect, and i'm just discussing one of the few if not only ways i find it not perfect. But give it 80 HP and it would be sheer perfection in my eyes aside from a few minor details, mostly cosmetic and fixable.(well, shocks, but i could easily live with the stockers if i had to)
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Re: Raise the Rev limit?
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Big Bore
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Big Bore
Joined: Jan 2005
Posts: 9,223 |
Actually, it did sound like you were dissing them!  And yes, they DO de-tune them. They'd be thrown in jail if they tried to sell them tweaked! Blame it on the tree hugging, PETA liberals!!
"Never underestimate the power of human stupidity" - Robert Heinlein
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Re: Raise the Rev limit?
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Joined: Nov 2005
Posts: 30
Greenhorn
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Greenhorn
Joined: Nov 2005
Posts: 30 |
most likely just the wight difference is what made the honda faster because if you weight twice as much you need 4 times the power with everything else being equal.
05 thruxton 904, still looking for carbs
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Re: Raise the Rev limit?
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Joined: Jan 2005
Posts: 8,639 Likes: 3
Old Hand
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Old Hand
Joined: Jan 2005
Posts: 8,639 Likes: 3 |
OK, the 450 is listed to hit peak power at 9000. The way they did things then, that means the redline is probably 9200 - 9500. The top speed is listed as 106. Stat sheets like that one usually use redline, tire diameter and gearing to get top speed. So, by that reckoning, the America would top out at about 118. Comparing 118 @ 7400 to 106 @ maybe 9500, certainly over 9000, shows a huge difference in gearing that could make the 450 seem quicker at low speeds.
To give you an idea of just how much of a difference gearing can make, I had a friend who worked his way through UCLA. Part of his income came from drag racing 1 car length in his stock 40 HP '31 Ford. The only car that ever beat him was a striped down '36 'T-Bug' with leather bands in the gearbox. Now, was the Model A a better car than, say, a 327 'Vette or a Chrysler 300C? Not unless your life revolved around acceleration for the first 14 feet.
Let's hope there's intelligent life somewhere in space 'cause it's buggar all down here. -- Monte Python
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Re: Raise the Rev limit?
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Joined: Jul 2005
Posts: 1,378
Learned Hand
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Learned Hand
Joined: Jul 2005
Posts: 1,378 |
Don't forget tho, he raised the 450's front sprocket a tooth too. But i'm just saying it's a close call in any case and shouldn't be considering the triumph is almost twice the size ! My point is simply that the triumphs are very detuned, and just the fact that allowing more air in with pipes and rejetting like i did made a difference i would almost call huge says worlds about just how detuned they are. Heck, some have said jsut removing the snorkel even on a otherwise stock bike made a good difference. I still stick to my original feeling that at almost 1/2 the displacment they should be so far apart in performance that we wouldn't even be having this discussion. What is it that i keep hearing......"there's no replacment for displacement" or whatever the quote. And weight differences are no more than normal for the difference between a 450 and a 900. If anything they're CLOSER in weight than the typical traditional styled bikes of those displacments. And in other cases a 900 will usually cream a 450. there just usually is no argument.
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