Ariel Owners Motorcycle Club

New build. Iron VH.
New big end, bottom end bearings, rings etc. But other second hand bits. 23 tooth sprocket.

Very very noisy from the start.
Doesnt get better or worse when hot and unchanged in the first 50 odd miles, despite altering the clearances timing and other obvious stuff. It sounds like I have massive clearances .......

Coupled with a complete lack of go. It will get to 55 with a struggle ....

It starts very, very easily. Revs up fine ( but noisy).
I have a carb on it from another working VH.

I put a 664 cam in ( it looked and was stamped like a 664) but I'm thinking I might have got the timing out or something... I have a single lobe cam and followers I can exchange in. Are the pushrods different lengths ?

hi my NH sounded like a bag of nails when i first running it , it turned out to be the pushrods not fitting properly

I have a similar problem though it seems to go ok you could hear mine clacking away just kicking it over, I suspected end float on the cam a F type there is about 20 thou on the cam but the cam followers have flats so I suspect them, kicking it over with cam removed and it spins smooth and quiet.

Push rods are different for 664 and single lobe cams, check the working length in the drags catalogue. Measure from inside the top cup to bottom of ball end.

Dave

John , what valve springs are you using, better to use the longer soft springs v422

Mine clatters as well but then it does go rather well. I run a 664 cam and single lobe followers, gives something approximating HS MKII timing. It is worh checking that the ball end of the push rods do seat in the bottom of the cup and not part way up the ball, using engineers blue or felt pen. The lack of go may well be unconnected but may be incorrect valve timing.

dave.owen wrote: ↑Mon Sep 05, 2022 9:28 pm 20220904_191622.jpgJohn , what valve springs are you using, better to use the longer soft springs v422

Head and barrel were originally on a 1952 engine,so I guess that had a single lobe.

I recollect that I made the push rods up to the dimensions drags gives.

Sounds like the timing side comes off for checking.

one question

I see that draganfly has camshaft and cam follower shims listed ?
I've never used them on any single cylinder bike I've had ( this is my sixth ...) and I don't think I've dismantled anything with any ...

I use them, to sort end float

I use them, too; but I can't hear or notice any difference whether they are fitted or not.