1956 top end noise

[joe]

Hi List,

I just got my Pan on the road after 4 years of piecing parts together. Its a 56 mostly stock with all new moving parts . Lower end was done by Truett and Osborn and Headhog did the heads. The cam is stock HD victory cam. The bike starts easily and runs great, I just don't like engine noise or noises I hear going down the road. Its not a lifter or a piston (I know those sounds well), its more like a choppy huffing/rattling.

When I start the bike up cold it sounds great but as I go down the road and it warms up I get the noise. Also if accelerating the sound is definitely less. I asked this question on the CAI list and a few commented that it was normal. I have no basis for comparison.

My best guess is I should go up one size on the pinion gear. I know too tight a mesh gives a whine and I believe too loose gives a lot of top end noise (maybe my problem?).

I have triple checked the timing and pushrods. The lifters are hydraulic. Any ideas?

Thanks!

Joe

[1950Panhead]

Joe,
Panhead engines make noises modern engines do not.
Huffing/rattling does not sound like gear whine or tight/loose cam gears.
I had a hydraulic lifter fail once, there was rattling, I replaced them with solids to test and left them in, you can test.
Don’t worry about imaginary problems; you will have enough real problems to deal with.

Jerry

[UPSROD]

Joe,
May be in the rocker arms. All three of my panheads are quiet and are stock with
stock lifters and steel pushrods.

[joe]

Interesting UPSROD, my rockers seemed perfect when assembled but I do have aluminum pushrods.

Joe

[Robert Luland]

When it sounds like it ready to blow up, it's running at its best. A sound I've learned to love. Bob L

[Bosheff]

You say the sound decreases upon acceleration. Usually with excessive clearances, noises will increase upon acceleration/load....bosheff

[rigidpanman]

how about a tight pushrod

[joe]

Tight pushrod...hmm. Actually I kinda wondered that myself. I was so careful to get them so they wouldn't rattle I may have gone a bit too far. I will check that tonight and re post. Last night I stuck sound deadening foam to the undersides and in-betweens of the tanks. I don't really expect much from this but it won't hurt.

Joe

[rigidpanman]

Damn things can be touchy,btdt