[gene03079]

I have a Honda 175 vert that is set up to race. the bike has SL350 24 slide carbs on it. I have the float level set up at 25mm.

The bike still seems to have to much fuel at idle. almost like the fuel in the bowls it to high. I cant get a good idle even at 2k. If I turn the petcock to off the bike is using up the fuel. As the fuel level drops a bit the bike moves up in idle from 1800 to 3000. Do you think that the floats should be set up lower in the bowl? It pulls strong with the lower level in a short test. Not sure how it would run long term this way.

The mains are 100 and the slow are 38

 

[66Sprint]

Gene, MOST bikes that are set up for actual racing have the timing advance units permanently set at full advance.....This makes them reluctant to/refuse to idle at the "normal" idle rev range.......I would check this first before I "tweaked" the carbs.

Regardless, "running them low on fuel" by shutting off the petcock is NOT a good thing. The associated "pick-up" in revs may be the mixture "leaning-out" due to the supply level in the emulsion (mixing) tubes being less than up to proper levels,(more air "sneaking past") and could result in a "holed" piston (or worse).... I would suggest you try setting the floats back to the correct 21mm level so the mixing tubes stay fully submerged in fuel..... If it still is too rich (or floods), reduce the jet size(s)...

Racers demand constant attention and are usually torn down frequently....If you want to ride this bike on the street, you'll have to go back (at least partially) to street-bike components and settings to get it to run properly in that venue.....If you're going to race it, it will probably die below a 2200+ RPM "idle" (minimum engine speed)...... That's just how it is..... :roll: Steve

 

[gene03079]

Steve Great explanation. I think I am looking to get the idle lower than I need to. 2200 is probably where it should be.

I will pull the carbs today and make the change.

This bike is just for Vintage racing. I hope to race it for the first time at Loudon on Labor day. I was concerned with idle due to the bike needing a bump start. It can be hell in a full leather suit on a hot day if the bike stalls.


Thanks for the help.

Gene