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Toothed grin

Pole position

I think the answer is probably and no. First the no, generally LED's aren't focused enough to work well as headlights. If you have your lights dimming when turn signals and brake lights are applied I would say 10 more watts is too much if they don't you will likely be ok...

It's red

train buckled

About $400

www.scooterworks.com/complete-engine--150cc-short-case--gy6-chinese-products-966.php#.Ujch-tLMDSk

There are probably better deals to be had and I think there is probably a guy on here that would let you have one real cheap but there you have it...

If you have never built an engine and this one got to where it's at now I don't know that I would recommend you rebuild the top-end. It's not easy for everyone and getting it all to run right after could be even harder...

The whole "calculations" above are flawed in a very fundamental way. Discounting horsepower as being necessary and leaving throttle position out of the equation altogether is the only way you can support any of that 1/2 page of pseudo-scientific investigation and conclusions. It is clear most folks have a fundamental misunderstanding of the difference between torque and hp and how it affects performance.

for normal mild street riding the goal is to have it look something like this.



That particular bike gets 35 mpg or so ridden with in an inch of its life. It is displaced 1800cc. Now my old Vespa got low 40's to low 50's for mpg. Why? Power. On the Vespa it was basically always wide open. I now ride a bike with 500 cc and get right around 50 consistently and have gotten as good as 58. The 58 was on the way down a mountain. The good mileage didn't happen because I was turning low rpm's (I actually was going a bit faster than I usually do) it was because I didn't use much throttle to maintain the speed. Low rpms don't necessarily translate into high mpg. If you are holding a bike WFO because it takes all she has to maintain the speed it doesn't matter what rpm your running so much, your mpg will stink. Now if you can get your rpm up into the meat of that hp curve you will need very little throttle to hold it there. So higher rpm with low throttle positions may be better than low rpm and high throttle positions. The engines are designed to run best much higher in the rev range than the assumptions above allow. This includes mpg. I always find it kind of funny that people think they know better than a team of engineers. The folks at Suzuki want to make a bike that performs well in "normal" riding conditions. For this particular bike that means commuting. So unless you are doing something else leave it alone. You may have gains in some ways but you will sacrifice something, physics demands it. If you are having to use more throttle to accelerate because you changed the way the power gets to the rear you will not see any mpg gains. I'm not sure how we can tell people they are thinking things through well when they have completely left out the main part of it. How do we discuss mpg and not ever mention how the modification proposed will affect throttle position (or how much fuel the bike is being given). Motorcycle engines are not designed to run like car engines at all. They need to rev if you never get a bike near its peak HP you will never see it's full potential. Torque curves are commonly much flatter than the HP curves and not as drastically affected by rpm like supposed above. The torque is what you will need to get to speed not maintain it. If you don't have the horsepower on hand even minor speed adjustments will require a fist full of throttle...

Anyway good luck to you guys. Try to remember Suzuki has been a contender at the race track for a very long time because they know how to make a bike work well. They know far more about it than anyone on this forum. Minor tweaks might work ok but think long and hard before you do anything major. If what was theorized above was reality I can assure you actual engineers would would encourage motorcycle companies to get that cutting edge stuff to the street. They actually have tried dual range transmissions in the 80's and guess what, they were miserable failures, why? They didn't work. One of the simplest things to do is to change the gearing. If major benefits could be had motorcycle companies would make it available. Try to remember the test bed for the experiment above was primarily a Chinese 125 that is not currently road worthy (somehow the final drive failed??) and by his own account never would run properly with the choke off. How do we even consider for a moment that he night be on to something. Folks have been trying that same garbage chasing that elusive dragon as long as sprockets have been on motorcycles. It has never caught on.

I used to change sprockets on my Dualsport because racing in the desert, riding to work, and cow trailing in the mountains are all very different things. Now I expected it to change things. To say you can do it on a street bike and your top or lower end won't be affected is garbage. The whole point of the change is to affect your top or low end...