no top end power

[nightmarcher]

Hi guys I just picked up a 54 and I had a few questions. The bike wasn't idling correct so the previous owner put a bendix carb on it which fixed the idling but now the bike has no top end. First it was starting to pop and now it seems to lose power as you go up in RPMs. The previous owner was suggesting maybe something to do with the heads, possibly valve guides coming lose, because the problem is intermittent. Any suggestions would be great.

[nightmarcher]

I forgot to mention, I pulled the plugs and one cylinder is sooty black and the other seems a little rich. Also the bike has solid lifters and I believe aluminum pushrods. Sorry this is my first panhead. thanks

[steve_wood]

Hmmm... could be a there's more than one problem. Can you do the following tests and report the results?

- Compression test

- Remove carb and check for leaks in the intake manifold
(if you need a kit: http://www.geocities.com/mbskeam/index3.html)

- Leaving the carb off, do a leak down test. Listen in the intake manifold for leaks.

Any details on the carb? Model # and size of the jets? Adjustment on the jets (if applicable)?

steve

[steinauge]

Nother thing on Bendix carbs is the O ring on the main jet\main nozzle\float bowl retaining bolt(all one part). If the O ring is damaged the engine will run very poorly indeed.I sure would run a compression\leakdown and a manifold leak test first.

[nightmarcher]

It turns out the front head had a broken exhaust valve spring.