JETTING FOR METHANOL

[jimg1au]

hi
i am building a pre 75 mx360 slider and would like to run the motor on methanol.can any one tell me the rule of jet increase for running methanol.running big 2 strokes on methanol gives them a boost to match the japs and jawas and other 500cc bikes
cheers
jimg

[Tim754]

Comp over 14.5 to start, biggest carby you can fit and take the main jet out and run a 5/16ths drill through it. Worked for my old 360  tim

[Maico31]

There is a proper formula for it but i can't remember it exactly, no doubt someone will know. Increase the flow through the mainjet by about 300%, i used number drills 30, 31, 32, etc and ran a 80 pilot jet and drill the needle jet bigger than the main jet also.

[oldfart]

After a days use run  98 octane thru the motor to stop it from rusting out the internals

[Doc]

where might one stumble across said methanol and will it send finances crashing? just curious is all, good ol' pump fuel for this weekend

[Maico31]

Doc methanol will hit you pretty hard in the pocket and your bike will guzzle it 3 times quicker than petrol. Plus fair bit of stuffing around to get it jetted right, and will melt a piston in a few seconds if too lean. Used to get it from shell depots.

[Freakshow]

But it does sound sexy dont it doc ....

[Lozza]

Petrol will melt a piston in a few seconds if your to lean.Ask around the speedway blokes they diminish supplies faster than a fleet of Hummers outside a private school.
Everything needs to be BIG, spark,fuel tap, breather, fuel line, needle  and seat, jet, thin needle, run as much compression and advance as possible to get the shite to burn.Buy a few extra pistons and your away.It can be your foray into tuning Doc.
Me I would take Elf 124 over it anyday, but no doubt you can get em going on it.

[Tim754]

Doc Lozzas ELF is the go! really! Tim Methanol is real good at turning motors, carbies to goopy stuck blobs as mentioned if not cleaned out, oh and never try it in any fibreglass tanks! you can have deadly serious chemical reactions. Just sneak a bit of R30 in with the Elf to make a heady scent MMM)

[Graeme M]

Elf 124? What is that and where do you get it? Is it something someone seeking to make a bike go good at dirt track would like to have?

[Lozza]

Elf 124, using that would probably be illegal so I wouldn't recommend using it You could use it on a practice day though!!! A well known racer here got a hold of a drum at the time of the Eastern Creek GP's and put a tankfull in an RGV, the effect was 'instant TZ' without changing anything.However if you get it on bare skin it will 'burn' and a solid whiff of it will make you pass out.If that doesn't make you fall over the $9/l purchased in a 50 litre drum might.

[Doc]

mmmmm..for as nice as all this performance sounds I think I'll stick to pump fuel my neighbor used to run his dirt track TM and speedway midget on methanol when I was a kid but he'd still finish at the tail end obviously an expensive little exercise..

[Hoony]

Methanol is tricky in two strokes, jetting will change with conditions on the day (temperature, altitude etc) i know of a sidecar racer (ex aussie champ on MX & Dirt Track) who had the brilliant Ray Fisher set his KX500 power Dirt track chair up on Methanol (or "fuel" as the old boys call it) it took a lot of development time and lots of lunched engines, in the end Ray put a thermostat from an outboard in the water cooling lines to stop cold siezures and finally got it jetted, the thing was a rocket (i swung on it for 1 meeting, never again).

 i too considered it for my CR250 20 years ago for dirt track events and i was going to get a tuner to assist, he asked me one simple question "are you prepared to lunch 3 or so motors til we get it right" my answer was a "no" due to the expense. this question is still relevent today. if you need more speed in your aging VMX days its more than likely you need to twist the throttle more !

[firko]

Lot's of folks reckon they've got the perfect methanol jetting formula but in the end it's an inexact science that is best sorted by starting with the biggest and working down. The 34 Amal Mk2 on my 'DT1 from Hell' started its life on a Weslake Speedway bike. To start the jetting process I bolted it straight on, using the stock Weslake jetting. The bike performed so well I never changed another jet. For the rest of the bikes racing life the stock Weslake jetting did the job beautifully. My theory after that experience is that a 250 2 stroke is roughly the same jetting as a 500 4 stroke. At least it's a starting point. A 360 would be a bit bigger again on the main I'd presume.

[firko]

I don't know how Elf 124 is to jet for but it'd want to be easier than the VP C14 I used in my 250 Maico at the '99 Dirt track Nats. We had the 250 on the dyno for days trying all sorts of jetting, oils, pipes and even switching from Bings to Mikunis and back and while we finally got it pretty right using the stock 36mm Bing and a Wheelsmith pipe, moving the back wheel HP from 18 up to 29, the cost was extremely high running temperatures and having to run it as lean as shit to run clean and produce horsepower. The bike hooted and was only beaten for the title on a points countback by Peter Lees awesome Methanol burning ported Elsinore but it cost me a motor in the end. I rebuilt it and ran it on Methanol after that and it ran as well if not better but with no reliability problems. Granted that was nearly 10 years ago so racing fuel may have improved a bit since then........Why would Elf be ilegal for Dirt Track Lozza? Does it have a nitro methane content?