May 20, 201412 yr Anybody know what the thickness of the stock 2013 300 EVO 2T is? I'm thinking of dropping some compression with a thicker gasket before this thing kills me.
May 20, 201412 yr Two base gaskets, one S3 flywheel weight, one black throttle tube, one S3 short pipe is the cats meow to tame down a Beta 300cc.
May 20, 201412 yr Two base gaskets, one S3 flywheel weight, one black throttle tube, one S3 short pipe is the cats meow to tame That's the info I have been interested learning. Dan, I feel your pain. When I first got the 300 it came with the high comp gasket. One of the first times I rode it, it shot out from me like a bar of soap. After putting the stock gasket on, the bike tamed somewhat but the tips in this post will likely be my next mods. down a Beta 300cc.
May 20, 201412 yr In would hold off on the flywheel weight until you have tried the other mods, some don't like the way the weighted engine responds.
May 20, 201412 yr Author I've had bikes with and without the additional flywheel. I actually like the power delivery without but I have to admit the screaming top end of this motor is just too violent. This weekend left me hanging on by my fingertips a few too many times. I've also considered a smaller carb to tame the beast but I think a small drop in compression will work well even though it's a pain to do.
May 20, 201412 yr Dan A smaller carb will make it more responsive at the bottom end and then lose some on the top end. The flywheel weight slows it down as to how comes on violently. I would try the black throttle tube first,along with the flywheel weight. They are cheap and easy to change and don't open up things like potential air leaks. What about gearing?
May 21, 201412 yr I've had bikes with and without the additional flywheel. I actually like the power delivery without but I have to admit the screaming top end of this motor is just too violent. This weekend left me hanging on by my fingertips a few too many times. I've also considered a smaller carb to tame the beast but I think a small drop in compression will work well even though it's a pain to do. Naw leave the bike alone. Change locations. Colorado or New Mexico where most riding is done above 7000ft. Issue solved.
May 21, 201412 yr My biggest 'Pain' when swapping the base gasket was ensuring all the headbolts were at the correct torque. Since I did not remove the motor, my 1/4" torque wrench could not get on 2 of them and switching to a crows foot will give a different reading from a socket. So I had to go by 'feel' on those two, but the top seems good. I'm curious how others have torqued the head without removing the engine.
May 21, 201412 yr Author You have no idea how much I'd love to change location. Massachusetts is.... It's late. I should go to bed before I get wound up about the peoples republic of Massachusetts where you are free to do anything as long as its approved by the grainola eating,Prius driving master class.
May 21, 201412 yr Hi Dan You are welcome to pop over and try my bike out . I have 2 base gaskets in. I havent ridden another 13 to compare but our sa importer made a few changes to tame it down. Slow throttle tube and 2 base gaskets. Said it helped alot but is now on a 14 factory 250 and loves it to bits.
May 22, 201412 yr Author Ok I ordered a .30, .50, and 1.00mm from Haven. Once they're in I'll drop the motor and decide what to put in. I notice from the spec sheets vastly different compression ratios from the different models. If I can keep the 300 grunt with the top end of the 250 that will be lovely.
May 22, 201412 yr Dan , as a ref point I would not go more than 1.0mm from stock as a maximum. So if it came with a .5, well then 1.5 max. You will know better when you see what comes out!
May 22, 201412 yr Author Yeah that was my plan but I'm the kind of guy that buys three of everything just in case. I made a spreadsheet that will calculate the new compression ratio by typing in the extra base gasket material starting with the compression ratio and displacement on the spec sheet. It's good to be an Excel wizard.
May 22, 201412 yr Author Hi Billy, Already geared down. The transfer function seems a little odd on this bike. There's definitely a point in the powerband where life gets real interesting real quick. I had the black tube on originally but didn't like the feel off the bottom. Hard to explain but I know you know what I'm talking about. I may try a little needle adjustment first. I might as well as I'll probably have to re-jet for a lower compression ratio anyway. Good think I like to tinker.
May 23, 201412 yr Are you running the v-force reeds? I allways used the Boyesen dual stage to settle the Shercos a bit. Cheap to try! I wonder just how a 1mm change does compute? Prolly not as much as a 7000 ft change in altitude! Edited May 23, 201412 yr by copemech
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