I’ve been reading threads for two days and can’t quite find what I’m looking for. I’ve had The BB 351 on for two years now and love it! But it’s time for the TM36/38 Carburetor which will be here in two days. I have the original header, two brothers slip on and the air lid top with the snorkel removed. I’m hoping someone at sea level has already figured out which jet size and needle is best to start with.

 

As a member here, I feel you deserve the truth - so here it is:

In the next few days, you will be learning that no one has EVER used a dyno or a (wideband sensor + readout) to developed proper fueling with the TM36.

All this forum can offer is various setups that various members claim will work well.

In other words, you will be trying out various "hand me down" setups that have only been "validated" with dyno-butts.

You'll be digging back many years in here to find them all. Unless there are a few members still here that are using the TM36 on a 351.

IMO, when you settle on a setup that seems to run the bike well (via your dyno butt ) , you should put it on a dyno to make sure the performance operations of the engine are fueled correctly, or within reason.


P.S. The setups involve waaaay more than a needle and a jet. The engine will seem to run well with horribly incorrect fueling - as rich as 10.5 : 1 and as lean as 14.0 :1 ... It is impossible to know without a dyno as reading plugs is no longer an option with ethanol'd fuel.

 

Thanks klxter. I wasn’t aware of the ethanol scenario. I don’t run ethanol in my scoot so that is some very valuable information!!