Bonneville America Forums Forums Technical Forums General Tech Too Slow

I bought a 2006 Triumph America new from the dealer this past September. I followed the break in reccomendations of keeping speed slow and changing RPM a lot.

At 1000 miles, I tried opening it up and was really dissapointed to find that the top speed I could get to was 90mph. I am now over 2000 and haven't felt much of an increase in power or speed. I called the dealer and they said that this was about normal for a bike this size. They said I could expect maybe another 10% with mods, but that was about it.

I am at about 7000ft elevation, so the air is pretty thin, but I have taken it down to 5000 on some rides with friends and haven't seen much improvement. Also, bottom end seems to improve on cold mornings (denser air), but top end is still 90.

Is this all I can expect from this bike? If not, any suggestions on how to improve performance and how much of an improvement I can expect?

Thanks
Matt

Sounds like an air availability problem. Maybe opening the airbox, removing its snorkels, modifying/opening the exhaust mufflers, and rejetting the carbs would help. These are inexpensive mods, but quite effective. Check the tech vault for particulars. There is a good website that "Dinqua" (Pat) (Dinqua.com)has with pictures about this kind of stuff, with the link in the tech vault:
http://www.bonnevilleamerica.com/forums/...age=0#Post89123

I agree. Air availability issue. I run 120 easily and get there fast. (according to my optomistic speedo) I am at 2,000 feet elevation though and there is a big difference between 2,000 and 7,000 feet as far as air density goes.

Definitely too slow. I picked up my bike with 625 miles on it. On the trip home, I ran it up over 100 mph, and it got their rather quickly and readily and there was a lot more to go, but I backed off because I was riding directly into a rather stiff wind of about 18 mph sans windshield.

Is it Becky who lives in Flagstaff too??? [nips off to check]
Yeah it is...
She'd be the best person to ask as she lives there.
Dunno if hers is stock, but I suspect not....

7000 FT.? Man, that's higher than Denver. Poor scoot must be running uber rich in that thin air. Time to free up the airflow a bit, maybe even reduce the jet size to match the locale. Have you looked at youor plugs to see if the tips are that sweet pale cocoa color?

Oh yeah.... top end of 90....definately way to slow. My America is happy cruising at 90..... on the 03 I bottled at 108 and there was a possiblity that she could have gone faster.

Ok, this may sound stupid but has it got the 34ps restrictor kit installed? Had mine off the clock a few times, and it'll do well over 100 two up. Not that I go mad.......very often.

Good point about the restrictor kit. Never saw one, but that would also explain it. It is supposed to limit the throttle opening. I believe it fastenes on the side of the carb to externally limit the travel of the rotating shaft that attaches to the trottle cable, thus limiting the throttle cable "pull".--I think!!

Thanks for the responses.
I don't see anything that looks like it is limiting movement of the throttle cable or the shaft attaching to the carbs.
I'll plan on rejetting as well as trying some of those other mods to improve air flow.
Any other suggestions?

Improving air flow is the best way to increase your power. Pull the snorks, put on some low restriction pipes, get a Uni or K&N air filter.
Even at 7000 feet, I doubt that you're running too rich with stock jets.
Look in the tech vault for Pat's jetting calculator. It may be on the "Dinqua site".

If you'll pull a plug and read the tip it'll tell you the story and guide you to the solution. You should be seeing a light, pale brown tip. I'm betting yours is dark indicating too much fuel and not enough air.

Speaking of the plugs. Its really hard to get at them with the pieces in front of them that I understand have something to do with emissions. Is there a kit that I can buy to bypass/eliiminate some of that emissions stuff or do those pieces serve some other purpose?

The parts you are referring to are part of the Air Injection or AI. Check the tech vault or do a search. A removal kit can be bought from newspeedmaster.com.

Air injection removal kit
The air injection system pumps air into exhaust cycle to help burn unspent fuel. People remove it to keep pipes from discoloring and to minimize decelleration popping. I took mine off because its vaccuum operated, one less thing to go wrong.

I pulled off the snorkel thursday night. Saw a pretty good improvement. I'll probably replace the stock air box, and remove a baffle from the exhaust.

But, before I go there, any other ideas? I pulled the plugs today and they looked very good.

You're on the right path, more air into the engine. Opening the exhaust will help that along by creating a free flow...

Put in a UNI filter and you'll get an additional improvement in air flow without having to do any additional airbox mods.

Uni filter is good seperate pods are better for air flow. Depends on what you are going for and what you want as an end result. Don't for get the better the engine flows the bigger the jets you need to compensate for more air. Don't over look the pilots when I first did my bike I left the pilots alone and when I put it on the dyno it was scary lean until a little over 4,000 RPMs then was almost perfect. So I had to bump the main down a little and the pilot up.

hey bro
i was messing with my america this weekend thought the snorkel was the crankase tube which i've conected to a K&N filter when i found out the snorkel was under the seat i took it off
oh i also plugged up the tube that the crankcase breather tube was in
it was hard to get 170kph i took it out to the motorway (freeway to you yanks) and the d**n thing went up to 180kph with no probs
short pipes with baffles help keep the flow free i think
my next job on it is gonna be 18t engine sprocket 133 main jets 45 air mixture jets
hopefully it will stop popping on decelaration and have better fuel flow we shall see
maybe one day i will see 120kph (in my dreams)

OK now I get it. I was totally confused. I even asked the guys on CT tech day if they understood what you meant. I couldn't get the filter on the snorkel part!! LOL It also sounded like you had blocked all air into your air box. The whole thing left me scratching my head! LOL

Get long slash cut off road pipes, remove AI, remove Airbox, get a set of perfomance coils, and a set of CR carbs, with open velocity stacks, put a K&N engine breather on the end of the pipe comming out of the engine, get the carbs set up to the spec, make your rear numberplate smaller so you dont have a sail behind you,
play near the red line through the gears i think you will soon realise that there is far more to that little engine throbbing between your legs than you first thought.

mind you i only found this out because things went wrong, now though i am so glad they did.

sorry dog i misunderstood what the snorkel was or even where it was
i took it of yesterday and yes it did make a differance
i still think if you want to make them fast you need a big bore kit and a turbo should do the trick
anyone out there turboed there america / speedmaster
i've seen t100 turbo charged but no custom bikes
if you have show your pics and let us know how fast they can get up too

Make sure the carb slides travel all the way to the end. It is not uncommon to have the throttle cables adjusted to the point where the carbs are not opening all the way.

PS,

I usally carry over 350 lbs. between me and my son and hitting the "ton" is no problem although I'm at sea level.

I had a Dodge Dart with a 318 that went like a bat out of h*** at home in Boston, but when I moved to Denver it would not get out of its own way, even after I had the carb re-worked and re-tuned for Denver it still ran like a dog so I know the effects of attitude has on an engine.

But I bought my frist Triumph in Denver a 71 750 Tiger and I have been all over CO. with it and never had any problem burying the needle no matter where I was.

Good luck, it will turn out to be something simple.