Other
question about an older motorcycle

Question Description

I’m stuck on a question and need an explanation.

I just got a 1981 Honda xl 500 and it wont rev out when we rev it up all the way it crackles and boggs out but when we suck on one of the hoses itll rev out with no problem what could be causing this?

Student has agreed that all tutoring, explanations, and answers provided by the tutor will be used to help in the learning process and in accordance with Studypool's honor code & terms of service.

Final Answer

The main jet was way too rich. We`d already done the basics: clean filter, new plug, valve lash adjustment, cleaned the carb with compressed air/carb cleaner and set the float height.

Amazingly enough the main jet on this bike interchanges with just about any Keihin motorcycle carb made around this time (70`s and 80`s)...maybe even later model Keihin carbs. I took a #115 main out of a spare set of carbs I bought for my old CB750 and tried it just for the hell of it and it threaded right in. Bike is definately too lean now (pops on decelaration) but revs out nicely and pulls like a raped ape. We ordered a bunch of main jets to try in the bike from #125 - #150 so we will get it dialed in correctly for sure.

Source
http://www.dirtrider.net/forums3/showthread.php?t=121267

Smartbrains (326)
Boston College

Anonymous
Solid work, thanks.

Anonymous
The tutor was great. I’m satisfied with the service.

Anonymous
Goes above and beyond expectations !

Studypool
4.7
Trustpilot
4.5
Sitejabber
4.4

Brown University





1271 Tutors

California Institute of Technology




2131 Tutors

Carnegie Mellon University




982 Tutors

Columbia University





1256 Tutors

Dartmouth University





2113 Tutors

Emory University





2279 Tutors

Harvard University





599 Tutors

Massachusetts Institute of Technology



2319 Tutors

New York University





1645 Tutors

Notre Dam University





1911 Tutors

Oklahoma University





2122 Tutors

Pennsylvania State University





932 Tutors

Princeton University





1211 Tutors

Stanford University





983 Tutors

University of California





1282 Tutors

Oxford University





123 Tutors

Yale University





2325 Tutors