HD ULH + M51 adjustment

[T. Cotten]

...,he freaked,YOU RODE MY BIKE?!!!I..

Did you charge him your time, or ride it for free, Duffey?

....Cotten
PS: My insurance makes me invoice everything.
PPS: I guess you missed my point about Tedd's.
PPPS: Back to topic: Antti!
Keep those commercial one-size-fits-all PEEK seals snug, and re-snugged, and snugged again...

[asavolai]

Hi,
I checked ignition, it okay.
I have one-size-fits-all peeks, so will tighten them. But after I change the manifold. I decided to change the manifold and M35TP carb back. If bike works after that, then the problem is in the M51 carb.
And the I need to check if venturi (and everything else) is backwards...
Thanks!
Antti

[asavolai]

I changed back 4 bolt manifold and M35TP carburetor. And the bike works very well. So there must be some odd in the M51.

Where to start? float level? Venturi?
I can just barely see light between venturi and body. Can that be the reason for problem?
I think there's not enough gas going to engine with M51(L)

[T. Cotten]

Antti!

There is only one float level: ¼ inch.
Beware of thick commercial gaskets, appropriate for M53s and the like, but use a different setting to accomodate it.

Usually a few small issues add up to make a tuning problem.
My approach is to fix everything, and problems seem to "come out in the wash".

Since its an acceleration issue, I would inspect the fit of the nozzle spigot within the venturi's hole.
(A steel (what were they thinking?) reproduction just crossed my benches with a .201" hole for a .1875" spigot. The manufacturer was obviously "lost in the woods".)
Worn holes can be saved with a very thin PEEK seal. Worn spigots can be sweated with soft solder and lathe-cut, or replaced.

....Cotten