Engine/Exhaust question

[Melton69]

Hey Guys,

I bought an 86 a while back and I could never seem to get it running right, low-end ran strong but about 3/4 to full throttle and it would bog down and back fire. I messed around with the jetting, replaced the reeds with v-fore 3, cleaned the petcock and a couple other things and it didnt fix it, messing with the jetting helped a little, but then I was always replacing the plug which was covered with oil. I talked to a friend from school whos a small engine mechanic and he said that maybe my exhaust was norrowed due to deposit. That made sense to me since it sounded like it couldnt get enough gas out, though it seemed that it was putting out a normal amount while running it. I have a PTR race pipe and fat boy muffler on it and upon breaking it down I didnt notice any deposits, the fat boy had a little depisit and the packing was really packed down and black.

Would this cause my problem? Could it just be that the packing was abstruction the flowand needs replaced?

I have the bike all torn apart now for a restoration but am planning on putting it back together in a couple weeks.

Any help is greatly appreciated.

Thank you,

Melton

[Melton69]

Anybody, help would be greatly appreciated.

[Ruf Racing]

I'm no expert, but to me it still sounds like fuel. Maybe the jetting
is to rich. Be patient, the big guns :muscle: will respond to your needs. ;)

[destey]

I'd bet money on the mainjet needing to be larger or smaller. Or at least some kind of jetting change needed

[312R1]

Here is what I would do to find the issue.

1. Do a leakdown test.

2. If that checks out I would try changing the main jet go down on size.

3. If none of the above fix it I would think it's electrical. I had the same issue last year and it turned out to be the stator.

-Steve