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Race Buell Improvement Thread

Buellxb Forum

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Stock motor, my XB12XT won't pull to redline in 5th, seems to be good for 131mph-ish, 6400RPM on top. Current gearing is 27/65, I see Evol Industries makes a 26t front as well as stock 27t... would I be able to get away with that with the stock belt to squeeze a hair more out of the Uly on top?
 
Stock motor, my XB12XT won't pull to redline in 5th, seems to be good for 131mph-ish, 6400RPM on top. Current gearing is 27/65, I see Evol Industries makes a 26t front as well as stock 27t... would I be able to get away with that with the stock belt to squeeze a hair more out of the Uly on top?



would I be able to get away with that with the stock belt

NO
 
Right, so chain drive conversion sooner rather than later, and decide how deep into a motor build I'm going to go for the second half of the season. Was really hoping with all the talk of relaxing the tension on stock setups that there'd be some wiggle room, but guess not, bah. I'm adding "Barrett said I couldn't" to my big book of excuses. :D
 
You may be able to find a XB9 front primary sprocket (and chain) to get some more reduction. That's on my list of things to do. You will need to find a 08-10 sprocket only that is held on by a bolt (not a nut).

I could have sworn there was a Euro-spec pulley/belt setup with different ratios, but that may have been for the tubers only.


Above all, WWBD (what would Barrett do).
 
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Chain drive will be the likely end game, along with breathing on the motor. Short term, I believe the full XB9 primary gearing swap would be too short and I'd be capping my top speed below where it's at now. It looks like I *can* source different length primary chains so there is room to chase things there as Evo Indus has a pretty wide range of primary sprockets to go shorter incrementally, and a 56T basket to go slightly taller while leaving the belt drive alone. That's worth exploring I think as a chain drive conversion, done right is NOT cheap, and I want to go aluminum primary anyways.
 
Never had a problem with a chain conversion done cheap. Thats my middle name!

Even on a few very hopped up 12's. I could absolutely tell a difference between the belt and a chain on initial throttle. Not having any belt stretch or cush drive made a noticeable difference. Kept a real close eye on the rear hub/bolts, and the nylon idler and didn't have rapid wear or loosening/cracking of the wheel:eagerness:
 
After a lovely sushi dinner with CoOter, it was pointed out to me that I may not be the best source of advice for race/track bike gearing. :upset:
 
I may not be either! I'm just a copy cat to what successful teams do. Way to dumb to think of this stuff on my own:black_eyed:

And Sushi was great!
 
And... this project is done. I was 13 seconds out of the qualifying cutoff in Q1, with a trap speed of 136.8mph vs 169mph, 5 more laps in Q2 wasn't going to magically close either of those gaps so I've packed up and am on my way home, the MotoAmerica shenanigans are done now. MA is strictly enforcing the qualifying cutoff for the class, and with the removal of the American AirCooled Twins subclass, the only two aircooled machines that entered that I know of were myself and a crazy built Polaris Victory in a custom frame that was having major running issues so also didn't qual. All of the Sportsters, Big Twins, etc from last year didn't show up, looks like there were maybe half as many entries as we had at COTA? Maybe they skipped Daytona on purpose and will show up at other tracks, but they'll have to meet the same 115% time of the Indians as everyone else.
 
Dang, that's terrible news just because you have to race with the big boys. They might change again if they can fill a grid? You could still club race though. It could be competitive in a more run-what-ya-brung class.
 
Last year they had to beat back the American aircooled machines with sticks, there were tons of big twins and modified sportsters entering. So many that at COTA they had to run a 'B' main. This was a combo of two things, first that Roland Sands required that Moto A give all who entered a main, and that the aircooled rules were basically 'please show up'. Because AACT was scored separately, there was no expectation of having to build your machine to match an FTR or Pan Am, your goal was to try and keep Hawk Mazi off the podium on his Indian Chief.

For this year there is a distinct change in the feel of the class, for starters they've allowed triples in, no idea why. The Yamaha MT09 is going to be released as an 'R9' any day now in the world's worst kept secret, and the Triumph 765 is just the sportbike version with bars, both brands can slot their machines into regular classes. To get these in the class definition was tweaked to allowing 128hp at the brochure instead of the original 120hp cap the class started with. To get the Pan Am in last year, they required it run the Sportster airbox lid and velocity stacks to choke it down as it advertises too much HP out of the crate, this year, just the lid is required so almost no restriction? Again, HD has bikes that are legal for the class without rules bending, the Sportster, the Nightster 975, but instead tweak the rules to let the Pan Am in and raise the perf target for everyone? Hawk this year is on a Pan Am, and the class has a ton more FTRs and Pan Ams running than last year.

My read is Moto A is now exerting control over Roland's head, they want to see more brands, hence allowances to get Yamaha and Triumph's sportier machines in instead limiting them to say, their twin cylinder already legal machines. They're also hard enforcing qualifying times, and got rid of the AACT subclass to weed out the actual hooligan machines to narrow the lap time gaps. Opening round of 2024 had half as many entries as COTA at the end of last year, but they got their HD vs Indian battle with both companies fielding BIG MONEY factory teams. There is a good chance both HD and Indian also pushed for this, they don't want their riders getting 'held up' by slow traffic?

Looking at my lap time splits, 10 to 15 more MPH would have made up a ton of my qualifying time gap. On the flip side, I can't read the Dunlops worth a damn so I'm timid on the brakes on corner entry, I'm using engine braking for 50% of my stopping power. Roll speed, again the tires don't talk to me so I'm more just guessing with what appeared to work the lap prior, or tagging on with others as targets, so seem to be doing ok there. The dogleg I should have been flat out through, never got the courage, bit bumpy mid corner. Exit, again, no feedback from the tire so I'm slow to open it up. Suspension will go a long way towards fixing those deficits I think? I'm pretty horrible at figuring out new tracks, got spoiled by years and years of only running Loudon, fortunately Daytona isn't that complex a layout so I was starting to put it together in my head decently after 11 laps.

Got some thinking to do short term, cost wise I got through this pretty decently. My trailer needs some serious R&R from the **** roads in NY and FL shaking it to hell... With the way the rules are structured now, the XB's out of the crate advantages over even heavily modified Sportsters / Big Twins mean nothing vs built modern sporty bikes. To have a chance I'm going to need a radical perf jump. If I could find an XBRR motor I'd be throwing it in there in a heartbeat. :D I'm half tempted to try and start the conv with Moto A / RSD to see what it'd take to just put an 1190 on the grid, have all three American MFGs with their current kit out there.

As far as local club racing, I've got no interest in racing my local series any more, and if I were to go back I'd honestly find a different machine. The XB amplifies all my riding weaknesses, I've never been good on heavy machines and much prefer ultralight class bikes or sumos. If I'm working seat time for MotoA that changes the calculous, but... gotta stew.
 
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I appreciate the low-down on whats going on. I was curious why the BIG change, but it does make sense the way you think about it.

I wanted to race AACT after lightweight because a 400lb, 120hp machine is a good 'step-up' without the bat**** craziness of the 200hp Gold Cup big dogs. Well, guess what happens when you grid up on an EBR 1190:upset:

And what the hell do I do with this extra XB-Ss now!?!
 
Current dumb ideas list / mental math problem:

Find a good condition primary drive kit, front sprocket, rotor, clutch and hub to send off to Evol Industries. I already know the 08+ XBs need a larger shaft OD and spline for the crank sprocket, there is some question as to weather or not Evol's stuff needs the backspacing adjusted or not. There is also the question of weather or not my STM clutch will work in the Evol basket. If I can source spares, I can send my STM clutch and a set of bits to Evol to eval. A spare rotor will also let me do a partial magnet-ectomy on one for race use. While that's happening the bike will still be usable so I can get seat time in at local venues, so I can try to learn how to ride on Dunlops 'cause they do NOT talk to me like Pirellis do and I'm not the type to just throw a bike in on blind faith.

Second item of concern, I hate doing this solo, at COTA I had a friend helping in the pits which was a BIG stress reducer. At Daytona it was the me, myself and I crew which required a LOT of doubling and tripling back and forth for things that should have been single trips. Before I commit to Mid Ohio, I think I'm going to need to lock in an actual 'team'.

I need to re-engineer my instrument cluster bracket, the OEM brackets were declared a 'fairing' so not allowed. I should get a weather pack / delphi connector kit and clean up the bodge done to the headlight harness while I'm there, make that disconnect-able as it was before. A custom seat/subframe would likely drop some noticeable weight too while I'm in the fabbing mood, not a small project though.

Suspension, that's a not cheap rabbit hole, and I've not had any luck finding used Penske / Ohlins kit to help with the cost. Is the OEM shock rebuildable?

XBRR rear wheel needs to be kitted out so I can use it, I should find a spare front if I can't find an XBRR unit so I can have a full spare set for rains.

Motor... do I want to chase down that even bigger rabbit hole?

Do I want to deal with any of this, or just bite the bullet and start putting the Uly back to street mode?
 
I also don't get along with Dunlops. Completely different set-up as compared to Pirelli or Bridgestones. Sidewalls to stiff, no feedback.

Hell of an experiment. I would punt unless you have lots of spares.
 
**** it, we ball!

I'm working with a Bueller on dropping weight from the driveline. I can't touch the clutch basket unfortunately due to my slipper crutch, but the rest including the rotor is getting a shave. That plus the XBRR rear wheel should unlock an HP or two. I'm waiting to hear back from another Bueller on a 'kit' to setup the XBRR wheel. No idea how I'm going to mount the instrument cluster yet, but will figure that out, I've got time before Mid Ohio.

If you don't double down on stupid, was it really a bad decision in the first place?
 
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