| Author | Message | ||
     Vospertw |
All, Took my bike to the big track at Willow Springs this weekend. Good learning curve with the bike, though I noticed I was not approaching the rev limit in 5th on either of the straights. Now, I'm a low end B group guy so there's room for improvement coming out of the turn prior, but at WOT and tucked as low as possible, I could only get to 6-6.2K or so by the time I chickened out, er I mean, started braking. I've been thinking of the swap since the first couple rides on the bike - just seems to be a geared a bit high for our tighter back roads - but wanted to see if I would really lose any practical speed at the track - which doesn't appear to be a big problem. I've done some reading in the Tech section, seems simple enough to do - are there any disadvantages or "others" that I'm not thinking of? Stressing any components, inviting some other failure, crappy mileage, excessive moving violations, etc.? Thanks! (Message edited by vospertw on June 08, 2010) | ||
| Glitch |
It's simple, no issues except keeping the front end down. But that's from a stop, so only an issue for you once a race, so launching will change. You'll get tons move drive out of the turns. It'll probably be one of the best/easiest mods you could do for that track, or similar track. On the street, you'll go from a 140, to 135 top end. Gas mileage won't suffer too bad at all. Moving violations? If you do lots of wheelies because it'll be easier with the lower gear, but it'll still be in your control. | ||
| 1324 |
^^ what Glitch said. My first Buell was an XB9, so I became very accustomed to it's gearing. When I picked up my XB12, the gearing was the first thing I've noticed that needed to change. While I didn't mind where 5th gear was, 1-4 were entirely too tall for my riding style. I found slow speed turns (turning city corners, parking lots, etc.) always put the bike in a funny position between first and second gear. On the open road, this wasn't as much of a problem, but unless I was on the highway I felt I was either over-revving fourth or lugging in fifth. Of course, this is based on my average speed on my usual roads...so in the 50-65 mph range. Bottom line: I wasn't very fond of the OE XB12 gearing. The XB9 gearing was a welcome change, and very easy to accomplish. Install only took a few hours, and the result was dramatic. The ~11% gearing reduction definitely pulls the front wheel up faster in first and second gears, so you'll need to slow your throttle hand down a bit. Slow speed maneuvers were improved considerably with no more of those funky in-between gears moments. Also, I found that the notorious XB12 surge was lessened with the gearing swap....could be due to the increased 'throttle response' (less time spent at a particular engine speed) or the fact I'm cruising at different speeds. To be honest, I never chased this down because it was no longer a problem. The shorter fifth gear is now a bit shorter than I'd like for highway cruising (~4500 RPM or so at 80 mph), but I can deal with it. The XB9 feels less stressed because the engine spins up higher and smoother. If only I could add a sixth gear for the highway...1-5 would be spaced perfectly. On the track, you'll run out of steam faster (I have on my XB9, anyway), but this might not be an issue depending on the track and your skill level. I've realized that some straights just have a point where I'm no longer accelerating - just high speed cruising to the brake marker. YMMV. If you decide to go through with the conversion, I recommend buying the superceded engine sprocket. The early XB9's had a heavier sprocket. I'm not sure if HD/Buell purged their supply system completely, so getting the old one might not be an issue. Either way, the XB9 sprockets are lighter than the XB12's, so you'll get less flywheel effect and more throttle response. Nice improvement overall, IMO. | ||
| Vospertw |
Thanks guys. I spent a lot of time on dual sports where you can run out of horses quickly due to drag. I always found that gearing DOWN was a better overall improvement for the bike than trying to gear up - easier on the motor, and an easier "performance" upgrade than trying to rejet carbs, etc. Guess I'll start saving some pennies and try to time it out for the 5K checks since I'll have it up on the lift anyway. Glitch - I'm not sure what my top end was on Sunday - we had to have the speedo taped over (I was planning to remove it on the last session just to check but my muffler strap broke) but at 100+ on the thermometer and 2400'+ in elevation... I'm not sure we were getting 140 anyway. | ||
| Greg_e |
What are you going to do with the stock gears/chain? | ||
| Vospertw |
Great question - I'm wondering if not having them available would hurt resale down the road. I generally keep all of that kind of stuff in case a new owner wants to return the bike to stock. In any event, will be a few months - just turned over 2100 miles - but keep in touch if you are interested. | ||
| Greg_e |
I might, would like to test dropping the ratio on my 9R for better cruising. Most corners still seem to be between first and second, but if I slow things down a little first might be the trick with the 300 to 500 rpm reduction that I would see. I say test because I'm not committed enough to drop the cash on a new set but would consider it for a used set. I thought there was someone parting out a 9 series machine that might have those parts for you. | ||
| Vospertw |
Greg_e - I'll keep you posted. I see an 03 being parted out - my understanding was that I would need an 08+ for my 09? Maybe I'm wrong on that - I saw something about a new gear for 08+ on American Sport Bike, and that the different year groups were not compatible. | ||
| Greg_e |
OK, then I can't use your gears either, yes I do believe you need the newer parts so it sounds like you may need new stuff not used. | ||
| 1324 |
Vospertw, I didn't realize you had an 09. In that case, you need parts from 08-10. The 08+ crankshaft's pin were larger than 03-07. | ||
| F22raptor |
And I am going the other way with my XB9R,geared to short for me...... | ||
| Greg_e |
I'm thinking mt 9R is also geared to short for my style and might want to drop it down that 11 percent. Would be slightly nicer on the highway, and I think it would allow me to corner in first where I'm now normally slipping the clutch in second. But mine's an 03 so I need the older style. | ||
| Jaylightnn08 |
I have an 08, isnt it possible just to switch the gears in the primary to get better acceleration lower top end? | ||
| Froggy |
Jay, yes, thats what this entire thread is about.  | ||
| Mgibson61611 |
Dumb question, does the swap impact the speedo? I have both an XR1200 and an '07 Super TT; I'd like to gear the XR up and the Buell down... too bad I can't swap 'em (oh well, the crank change in '08 was a good thing...) Cheers | ||
| Froggy |
No, the speed sensor is part of the transmission output shaft so being that the change happens before power enters the transmission, it won't affect the reading. If you changed the belts sprockets to something else you will affect the speedometer. | ||
| Vospertw |
I did a search through the tech vault and found the following dimensions for a lock bar - 4 1/8" L x 1" - 1 1/2" W x 3/8" H. Sound about right? It was an old post, just checking. | ||
| 1324 |
Those are the right dimensions. You can get by thinner plate for steel...3/16-3/8 will work. | ||
| Jaylightnn08 |
I meant just switch the 12's gears instead of swapping for xb9 gears | ||
| Vospertw |
1324 - Thanks. We have a pretty decent industrial metal shop in SD that has just about everything. Should be no problem picking either. | ||
| 1324 |
I meant just switch the 12's gears instead of swapping for xb9 gears I presume you are referring to switching the crank sprocket for the transmission/clutch sprocket? If so, no. There are numerous reasons why this isn't feasible. But above all else, it won't help you. The clutch/transmission sprocket is larger than the crank sprocket, so you'll lose acceleration - by a LOT. The stock XB12 primary ratio is 1.5 (57/38), and reversing them would give you 0.67 (38/57). Fifth gear would idle around 50 mph. (Message edited by 1324 on June 10, 2010) | ||
| Slaughter |
Big Willow gearing means that you're setting to be just short of rev limit at the exit of 9 or end of front straight (whichever is faster for you) On less-than-superbike HP (like the XB) - and if you have the wrist (and the experience) - the fastest point on the track is the 8/9 transition just before you roll-off and turn in on 9 (NO BRAKE turn-in at about 120-130MPH). I've got my bike geared for that point. Stock gearing on ANY bike is way too tall for racing. True for Buell, Suzuki, Yamaha, Honda, Kawi. They are all geared for EPA noise and smog and slower turning engines means more engine life. Gearing down the XB will make it come ALIVE at Big Willow... but now you're talking a chain conversion (cheaper than a Baker tranny) if you are REALLY gearing it down. I assume you have an 12, not a 9 - and are talking about converting your primary to the XB9 gearing? That'd be more appropriate than the stock gearing on the 12 at the Big Willow track. (Message edited by slaughter on June 10, 2010) | ||
| Slaughter |
Oh and if you EVER come up here to Willow again, give me a shout, I'm always up for an excuse to do some tuning/training! | ||
| Froggy |
Holy crap, the fuel economy would be epic! I will have to look into that further | ||
| Greg_e |
It would also be the type of gearing for a high speed run on the salt, if you could put enough power through to get it going fast. If you always idle your bike, you will clog the cylinders. You'll be changing plugs every ride. | ||
| Froggy |
My bike doesn't get much above idle anyway, and if I can extend my 270 mile cursing range and break the 300 or 350 mile mark, I can finally sell the Blast | ||
| 1324 |
Yes, CRAZY high speed gearing. For an XB12 (assuming 6700 RPM redline): 1st : ~115 mph 2nd : ~165 mph 3rd : ~215 mph 4th : ~260 mph 5th : ~305 mph Doesn't account for drag, obviously. Since drag increases with the square of speed, we're talking some serious numbers. But in a vacuum... Either way, you'd need some SERIOUS grunt to get going that fast. Froggy, you're the first volunteer... | ||
| Rudolf35 |
I am waiting on my new primary and have one question: What is the socket size needed to remove the drive and clutch fasteners? | ||
| 1324 |
The engine sprocket was either a 28mm or 1-1/8"...Someone else might be able to confirm. I recall clutch using larger. 30 mm, maybe? Either way, I have all sizes up to 30 mm and didn't have to buy new tools. | ||
| Sifo |
The stock XB12 primary ratio is 1.5 (57/38), and reversing them would give you 0.67 (38/57). Fifth gear would idle around 50 mph. The ratios don't get reversed. They just get changed to what the XB9 uses. It's like a 10% or 11% change. Which means that... 1st : ~115 mph 2nd : ~165 mph 3rd : ~215 mph 4th : ~260 mph 5th : ~305 mph is way off. |
