| Author | Message | ||
     Chevnut55 |
Most of us know our bikes should have been built with a 6 speed..the 5 speed doesnt cut it on the highway around 4,000 rpm all day is not much fun for the bike or the rider. does anyone know where you can buy a different front or rear pulley to gear it up? I do know you can gear it down for low end power..I dont know why thats needed!!! whats needed is a 2 tooth larger rear or 2 tooth smaller front pulley. I do not want to invest a ton of time and money tearing into the bikes trans or anything or the expense of a chain conversion..just a pulley swap that can be changed back after a road trip if wanted. So can anyone make anything like this? if not why? | ||
| J_dickau |
Steve, I think what you want is a larger transmission sprocket and/or a smaller rear wheel sprocket to reduce engine speed at a given vehicle speed. Some sportsters have/had 28 or 29 tooth trans sprockets but I am not sure if it will fit and you may have difficulty finding a belt. Xb9s have 34 tooth primary engine sprockets and XB12s have 38tooth engine sprockets so switching to an XB9 engine sprocket and chain is going the wrong way for you. Good luck. | ||
| Chevnut55 |
j, yes right got it backwards. They sell kits for xb9s but they only use 12b12 pulleys. Dont see why with all the aftermarket stuff we can get we cant get a set of gears. Im probley going to sell my bike because of it. I was thrilled in every other way..until I hit the highway. | ||
| Froggy |
You can get a taller gearing kit for the primary chain, which will lower the cruising RPMs on a XB12. I believe SRW Moto sells it. Due to the XB having a non-adjustable axle, there is no way to compensate for proper tension with gearing changes. The 1125R has a similar issue. The 1125CR has 8% shorter gearing than the R, and this is done by a different belt, rear sprocket, idler pulley bracket, and the real kicker: a slightly longer swingarm. The XB is fine cruising at 4000RPM all day, but I do recommend you slow down, you will save a ton in gas and speeding tickets! | ||
| Chevnut55 |
Thanks froggy,I can not seem to find srw . Would a pulley change work with a adjustable belt tensioner? Im about 4000 rmp at 70-75 thats what everyone in cars are doing..I should be going a bit faster than the cars to be safe, but when I ride with real sportbikes doing 80-100 I cant stay up without feeling like the motors going to blow. | ||
| Froggy |
I went looking for it, turns out SRW Moto closed down for good a few months ago.  I really don't think an adjustable tensioner itself will be enough. Personally I think your best bet is to convert to a chain drive, it will cost less than finding new belt sprockets and belt. A chain conversion kit will set you back about $200. 4000RPM in 5th gear on a stock XB12 is 80mph, and 4000 in 5th on a stock XB9 (or XB12 with 9 primary chain) is 72mph. It sounds like you may have have the XB9 primary chain swapped in. | ||
| Chevnut55 |
Thats too bad, these companys that make us parts keep closing..makes me nervous about keeping this thing for a long time. That would be great if someone did swap it on my 12, anyway I conferm it had a 9 chain/sprocket without pulling off the primary cover? | ||
| Husky |
Use a GPS to monitor speed and see what the rpm is at 80 mph! If its 4000 then as Froggy said, you have the XB9 primary gear and chain in your bike. husky | ||
| Tpehak |
Stock Buell XB front to rear sprockets ratio is 2.4. I have 240 mm rear wheel with chain conversion with 50 teeth rear sprocket and 23 teeth front sprocket and it gives ratio 2.17. I did not set this ratio intentionally, this is what parts I found and they give necessary chain slack. I was too lazy to figure out necessary amount of teeth for sprockets and to build custom sprockets to keep stock 2.4 ratio with appropriate slack on chain so I just ride it with 2.17 ratio sine it already had appropriate chain slack. So after many miles on this gearing ratio I'm telling you this ratio sucks in the city. Your minimal speed at 1200 rpm at 1st gear is 15mph. You constantly have to work with clutch at low speed in the city, you constantly rubbing you clutch friction plates. As result I already went thru 2 clutch plates sets, they last just 4000 miles in the city at stop and go traffic wit such ratio. After about 4000 miles of such abuse clutch plates start slipping and you have to replace them ASAP because of once you feel any clutch slipping it will escalate exponentially fast and literally after a few hours of riding on slipping clutch you will not be able to do more than 30mph on the highway because of wind resistance. When it happened on me first time I ignored it and kept riding because it did not feel too bad. But next day on the highway it scared shit out of me when I was not able to go more than 50 mph at 5th gear. I had to shift down to 4th or even 3th gear to reduce clutch plates load and to be able to keep at least 60 mph on the highway. And of course it completely lost acceleration ability. So if you do a lot of city riding, don't go lower than 2.4 ratio. Now I decided to order custom 22 teeth front sprocket. It should still maintain acceptable chain slack with 50 teeth rear sprocket on my 2009 Buell XB12 Scg and it will be slightly higher closer to stock ratio. (Message edited by TPEHAK on January 07, 2020) |
