Anyone ever actually used motorcycle carbs??

[colster3]

Have been reading all the great stuff on putting the 4AG into my AE71.

Read on Phil Bradshaw's page about 41mm Keihins. Has anyone done that? Don't want to register the car but looks like a good alternative to $$$ for an ecu

If there is a thread about this, please add the link so that I don't bother you guys needlessly

Colin

[2jzhilux]

41 mm keihin carbs are about 400 each second hand

[Billzilla]

I use them on my racing car engine, and they haven't been sorted yet but when they are they should be pretty good.

[colster3]

Thanks Bill, I am building a club car not to be registered and thought that these carbs might have been of a production motorcycle GSXR or R1. Using a 100kw 4AG with mild cam (haven't decided yet) and the usual suspects, mild skim, lighter flywheel (similar to the ones John Henderson makes) so thought that the carbs might be a cheaper alternative for an old mechanic like me to tune and fit

[Turdinator]

How do you tune/jet motorcycle carbs? And why would you choose them over something more common, like DCOE webers?

[Vios-GT_07]

How do you tune/jet motorcycle carbs? And why would you choose them over something more common, like DCOE webers?

good question.. far as i know the old AE-86 rally cars used DCOE 42 or 45 webbers..

[colster3]

Tuning them I presume is the same as tuning motorcycles. Changing the needles like with SU carbs. Was a thought as I have more experience with SUs and CD Strombergs than Webers.

Looking for the most cost effective means of providing fuel to the engine. I am also keeping track on another thread where the author is thinking about using Mega Squirt. I have the injectors and the loom for this engine but initial research into microtech and ems seem to be quite expensive for a no-budget racing team such as mine...

[-==L=a=N=c=E==-]

although you say that, the 4age microtechs pop up every now and then. And they are a pinch to tune as well...

[briney]

motorbike carbs are cheaper to buy than webers. ( generally ) they are simple to tune. the tricky bit is getting the emulsion tube right. they have a main jet, which does 7/8 to full throttle. the needle does from about 1/8 to 7/8 throttle. pilot jet does the idle stuff. one thing to keep in mind is that you may have a 45mm weber, but with a 36mm choke in it. a 41mm bike carb has a 41mm hole in it at full noise.

[mrshin]

If you're really desperate, I suppose you could grab some Dellerto's from an old Alfa, but being how truly evil those things are, I'd highly suggest against it. Keep an eye on classifieds, ebay, etc. and see if an ECU pops up, and then use injection if at all possible - maybe you can use some gutted out carbs for throttles?

[colster3]

thanks guys, not in a big hurry but just thought the bike carbs looked like a good alternative. Will keep looking for a used microtech or similar

[Hiro]

When doing some background research for FSAE I read that there have been some problems with using motorbike engines and engine components in 4-wheeled cars, as some of the stuff isn't designed for large lateral accelerations (leaning over in the motorbike negates most of these). Whether or not this is a huge issue I couldn't get a concensus on

[Billzilla]

When doing some background research for FSAE I read that there have been some problems with using motorbike engines and engine components in 4-wheeled cars, as some of the stuff isn't designed for large lateral accelerations (leaning over in the motorbike negates most of these). Whether or not this is a huge issue I couldn't get a concensus on

I've seen a huge number of hillclimber cars with bike carbies, so don't think it's too hard to solve.

[andrewvibert]

We ran a 2TG with bike carbs for years. The biggest problem we had was that most bike carbs were gravity fed and could not cope with much fuel pressure from a pump.

[thechuckster]

bikes also make good donors for ITB setups on small 4 & 6 cyl engines.