Bonneville America Forums Forums Technical Forums Performance Mods BB904 installed!

D&D Cycles, Pensacola, FL installed their BB904 kit on my bike this week. They use the Wiseco pistons but bore and re-nickel the cylinders like the factory ones (no sleeves). They ran pre and post dyno runs, and a third after resetting carbs. I am getting 65.54 ft. lbs. of torque at 3400 rpm. The hp shown is not a max. hp as they did not want to do a high rpm (redline) test until after it is broken in. They plan to do another dyno run and recheck the bike after 1000 miles. The max. hp shown on the chart is 65.4 hp at 6152 rpm, but when the dyno quit measuring the hp curve was still moving upward. They estimate low 70s at the higher rpms. I'll post that one later.

There is no doubt the bike pulls much stronger than ever before. At 5250 rpm the bike is near 60 hp and 60 ft. lbs. of torque. More low end torque was my goal and this is definitely the way to get it. I've put 150 miles solo on it and plan to do some 2-up riding tomorrow. The bike even sounds better. It's slightly louder and has a lower pitch. I'm taking it easy for 500 miles before I start really playing with it. At 1000 miles the dealer will re-check everything, see if the setup is still optimum, and do a full (to redline) dyno run. Can't wait to ride some more.

I took it back to them today after picking up yesterday. It had really loud decel popping. It took 3 turns out (pilot screws) to control the popping, so they decided to swap the 42 pilots for 45s and it ended up 2 turns out. Popping is now about the same as before the BB.

Sounds really interesting Bob, keep us informed how she runs etc..

well more torque is what I'm looking for...hopefully next summer BB will be done kit waiting already

can't beat a big bore kit for torque! Enjoy!

glad your happy. cant wait to finish mine up and try it out. then put it away for snow have fun with it and i am in a hurry to see what that thing does totally unleashed

Frank

Sounds really good, now I'm jealous again.

mike

I rode another 100 miles or so with my wife 2-up today. It's like a whole new bike. With the increase in torque and hp, there is practically no difference solo and riding 2-up. I'd always had thoughts about possibly going back to the 17T sprocket, but no more! Although the gears are taller, the bike accelerates and pulls through the gears like never before. In every gear there is more power and usable range. I still haven't been able to really go for it as I'm trying to take it easy the first 500 miles, but it's like I own a sport bike now. I can't express how much difference the BB did. All I can say is I could give a crap about a larger twin cruiser right now. I've always loved the handling and look of my bike, now there's this huge difference in power.

If there had been a $1000. or $1500. option for more power and torque when I bought the bike, I probably would have paid it. The difference is worth way more than that. I wish I'd done it sooner.

Awesome numbers. The BB campaign does a great job on those engines.

A set of 130 mains & stock needles and pilots may be just the ticket to clear up the popping
without going too far into running rich. That way the fine tuning aspect can be shifted to the
more incremental method of shimming the needles. You might even get an extra HP or two.
From your signature data and dyno chart I would believe it's just a hair lean right now.
I could be wrong.

The decel popping is fine now. I like to hear some decel rumble and pops (and should) with less restrictive exhausts. They felt after many similar runs, the 125 mains are fine. Changing to the 45 pilots took care of the loud popping without having the pilot screws out too far. They prefer keeping the sniffer showing 3%, but mine did end up a little richer (4-5%) at idle at the best run setting. On the next dyno the initial leaning should be gone. It still might lean out a bit near max. throttle, but if it keeps the bike the best through the range I mostly use, it's fine with me. The bike does run noticeably better than the way it was set up when the last dyno was done. I guess we'll get a better picture on the next run. Meanwhile, I'm having a blast riding the bike.

Ok RamSound, if not asking to much, what was the price for the total package including installation?

I'm sorry, it's the barrels they swap out. Good thing it's not me doing the work.

That price sounds a lot better than the $2k some people have paid. TO and from work is 108 miles, half interstate-half state hwy. My 790cc engine is plenty. However, I catch myself thinking about the BB kit now and again. It's funny, I don't NEED the extra power, I just WANT it.

With that being said, I'd have to ride a bike w/a BB kit to see if it's worth the money.

I have a spare set of barrells as I thought about doing the BB kit, but my local engineering firm want £400.00/$800.00 just to put the sleeves in. Haven't got a clue what he would charge for bigger valves etc in the head.

So that has been put on the back burner for wee while.

Man I wish I lived closer to a place like that... Anyone know of a shop doing it in the NY area?

Man, you're only 400 miles away...that'd make a stellar vacation trip. Just think of it, a couple of days at Fort Walton beach and ride home on a BB...

if you have a set of barrels all set you can easily have the bike done start to finish in a weekened

Frank

You can buy their BB kit (they may be shipping one to Australia). You would need to send them your barrels. $895. + shipping for a complete drop in kit. You would have to do the work yourself or find someone up there.

Unless you want head work done.... Right?

correct, unless you go through bill who has an extra head already done.

Frank

OH he's got the head AND barrels done? Hmmmmmmmmm

Here's a comment from the dealer that did my BB install:

Thanks for the posting, I hope we get a little business from it. Many people go for the Wiseco kit not taking into account the machine work required, the down time and extra expense. I know the nikasil will last the life of the bike and not need a rebore after 20,000 miles like the old bikes did with steel cylinders. Thanks Bob, and we will see you when you get some miles on. Robert

They have rebuilt bikes with the Wiseco sleeves kit. They now only offer their bored and re-nickeled kit. They don't feel the reliability is anywhere near as good. If you add the cost to get a machine shop bore your barrels and install the sleeves, it might just cost as much as this kit that's drop-in ready and keeps the bike like factory with no sleeves or dissimilar metals.

Both kits should offer the same performance results if properly tuned and setup. I stand by my comment that the results are worth the money whichever way you go.

So is it true he has both the cylinder pieces AND the heads pre-machined and ready to go? So this makes it literally a bolt on...

Ben, it is truly a drop in kit. The barrels are bored and re-nickeled (like factory). The kit comes with the barrels, seals, gaskets, and Wiseco pistons, etc. You would need to swap your barrels in, or if you want to wait, they will redo yours. There is no other head work. I'm getting 66 ft. lbs. of torque and over 70 hp (haven't measured max. hp yet).

Check out the link to their performance site I posted earlier in this thread.

How do they do 10:1 or 12:1 compression with the 904 kit?

Wonder if the cams they sell are their own grind or if they are reselling (T-bike's?)

They offer two different pistons with the kit (same price). The higher compression ones look just like the Wiseco but with the tops slightly dished out. I opted for the standard 10.5:1. I'm still using mid grade gas and haven't noticed any ill effects. The higher compression ones give it a bit more hp boost.

I don't know about the cams. The high compression pistons and the light weight flywheels are their design and they have the work done.

OK So if I wanted head work I'm on my own... Makes sense. Anyone know of a head swap program?

bonneville poerformance does it. but his headwork aint cheap

Frank

Yeah... Maybe that could be like NEXT winter's project...

Ha!! No, but she is a teacher in about the only place in the world teachers get paid half way well... But I figure the price isn't too off the wall for the BB swap, and then I could do the head another time, devide and conquer!

Ok, so what's the disadvantage to doing the 12:1 kit? How soon will it blow up the engine? I mean, that's a big jump... but if it works, why not, right?

Y'all are making me all sorts of warm and fuzzy here, just sos ya know. Moo hoo ha ha.

For the kit, do they require a core exchange? It's cool if they do -- makes perfect sense -- but just want clarification...

Still, if the 12:1 is as reliable in the long run (theoretically) as the 904, then my concerns bout the 998 kit are worthless -- I'll just go with teh 904 high-comp. Tee hee.

I love these mills. I really do. Gotta love the Limeys who overbuilt these things.

--Jaeger

the biggest problem with 12:1 would probably be finding fuel that runs right in it with no octane boost added. Would put a little more stress on the bottom end too, old bikes could take it not sure of these engines.

if you want a reliable jump in power i say 904. many have runs it, tons of miles on them and they have been rock solid reliability. if you want top power go for one of the newer 1100 or 1200 kits that still run 10.5 compression which is perfect for a street bike. but money is needed for the larger kits

Frank

D&D Cycles claims there's no problem using pump gas with their 12:1 kit. I would guess you would need to burn premium for sure. I opted for the 10.5:1 kit and have been burning mid grade with no problem. Also, I knew the standard kit would give me all the power I wanted. Personally, I think a 12:1 is high for a street bike.