I've been contemplating converting my trx250r to run on methanol. I was wondering what i need to do to do this. I know that i need to convert my carb but couldn't find any info on doing it. Is it possible to convert my Keihin 39mm PWK to run on methanol and if so where can i get the kit. After i convert the carb do i need to get an alcohol fuel pump and different reeds also. I just got a esr 330 kit with a special dome for race gas, am i going to need to get a different dome will the compression be fine. Do i need to change plug type and if so which plug do i need. Any help would be apriciated thanks.

 

I have a 40mm Lectron dual power jet carb set up for alcohol for mine. I'm sure the 39 PWK can be modified for alcohol but I would suggest getting a Lectron set up by Dennis Packard, see here: packardracing.com. If you stick with the PWK then I would say to smooth bore it to 40mm or 41mm and go way rich on the jetting including gettinga new needle. You may have to drill the main jet to get to a large enough size. I have an ESR fuel pump and also drilled out my fuel petcock to allow for the increase in fuel flow needed. I also have an adjustable timing plate. With alcohol you want more compression than with gas; I'd say at least 200 psi cranking compression. I run an NGK Platimun plug and don't recall the number but I know they cost about 7-8 bucks each! Also remember with alcohol you have to purge the motor with gas/oil premix after a weekend of riding since alcohol is corrosive and hard on the internals of the motor, especially seals. That reminds me, I haven't purged mine since I last rode it about 6 months ago. Oh well, I'm gonna rebuild the bottom end anyway and put a 350cc jug on it in the near future.

 

hey thanks for all your help....Have fun with your bottom end rebuild, im currently in that process right now since i blew my tranny with my new 330 kit. I'm still looking for info on moding my keihin 39mm pwk since i just bought it a couple months ago if anyone has any info

 

Once a keihin carb is modified for alcohol then there's no going back to gas. The needle jet has to be drilled and is not a replaceable item. Just be sure of what you do first and definitely do the homework.

 

they are replaceable, just not sold seperately.

methanol is an oxidizer which is why you need to purge it. meaning if you dont purge it will cause rust to form on your crankshaft/bore. it isnt very hard on your seals though, but it will gum up inside your carburetor as well.