Hello
My start my matchless engine it runs very good but the timing gear is noisy ,I try to change the pignon but it's alvays the same, May this moise be normal?
It really make an pignon sound and, the sound dont come from the magneto or generator, I remove them , it's the same.
THank you for help
Sylvain

email (option): sylvainharle50520@orange.fr

A friend had this problem recently and it was the tappet guides badly worn.

Cheers
Pete

email (option): petercomley@web.de

When I start my G3 or my AJS I can hear the gear running, but not overly much, it's audible, but not noisey, so perhaps, as Pete says, you have some bad wear that needs looking into?

Hello
thank you for this help, my moise is not very audible at low idle and a bit more when the engine turns faster.
I opend the timing gear ,the gears seem nice ,the valve lifter have no play (the head is mabe a bit used )but no big problem.
The only think I am not sure is the valve spring , I'm not sure they are original ,May they be too hard?
Many thanks
Sylvain

email (option): sylvainharle50520@orange.fr

If it's that bad Sylvain, it sounds like something must be wrong or worn out somewhere, but without hearing it or standing next to it, it's difficult to say what it could be? It's certainly not something I've come across before.

Let the engine get well warmed up when its cold you will not know where the rattles are coming from

email (option): cooperbaumber@yahoo.com

You need to find out where the noise is coming from. If you take a large screwdriver and put the blade endnonnthe cylinder head and put your ear to the other end you will be surprised that you will be able to hear the engine noises from the head. Then put the screwdriver lower down by the valve gear and have another listen. It should be clear if the noise is coming from the head or the valve gear. It is likely that. The tappet blocks are warn and will need replacing. I would also change the timing pinion if you want a quiet engine. Don't forget the nut that holds it on hasnanleft hand thread and you will need a puller to get it off. Tappet blocks and pinions are both available from Russell motors. There is also a special tool for removing the tappet blocks although I do not know where you can get one from. I have one and can send you photos but will not lend it out any more .

I also have a very good article own rebuilding these engines and will send you a copy if you send me an email to my address above. Cheers John

email (option): Tinley@btinternet.com

I had a long period of trying to eradicate a valve gear noise on my G3. This culminated in a full rebuild of the engine. I found that the inlet rocker shaft had about 1.5mm end float and so was clacking back and forth. I put a hard washer in to eliminate the end float and the noise has stopped. Of course by then I had replaced big end and mains, cams, followers, valves, springs, piston etc. But I'm sure it was the rocker that was causing the heavy metal tapping noise. You can probably check them through the tappet inspection holes (Not present on a G3L though) Ron

PS. John I don't blame you about the tool issue, but I hope it was nothing I did??

email (option): ronpier@talk21.com

On a completley unrelated, but similar topic to what John was saying, I found a photo the other day of some WW1 soldiers laying on the ground in no-mans land listening out for German tunnellers beneath them. One of them has his bayonet laying point end on the ground and the handle to his ear, in exactly the same way as John suggests using a screwdriver to listen to your engine. No help at all, but quite interesting I thought?

Ron, absolutely nothing to do with you. JT

email (option): Tinley@btinternet.com

I found the tool, after a long search, there are a couple of parts missing, but nothing serious, have the laser drawing of the big plate, so could have some made? (very heavy to post) the small parts I still have to draw up.





Cheers,

Lex

email (option): welbike@welbike.net

Well done Lex. Johns tool came with just one of the screw blocks. Which is all you really need for removing one at a time. I'd say pretty impossible without it. Ron

email (option): ronpier@talk21.com

Yes, only one of the blocks is needed, but think I'm missing one of the little spacers??

Have also seen a picture somewhere of an old timing cover, that can be cut off/open, to substitute for the big heavy plate, but if it's as strong??

Lex

email (option): welbike@welbike.net

Hello
and happy christmas
Thank you for this help, I drive the bike this week ,I'm sure the noise is comming from the timing gear
When the engine is hot, the noise is less, and you dont hear it at low iddle.
IT 's not an claping noise ,so I dont think it's the tappet , I will try to change the pignons, And tell you about.

Many thank's Sylvain

email (option): sylvainharle50520@orange.fr

Personally, I have an aversion to sticking a bayonet in my ear.

I much prefer a wooden dowel about 18 inches long for a bike.
A broom handle works on a car.

email (option): britool51@hotmail.com

Just so long as you take notice of which end is pointy and which end isn't, you'll be OK Robb. Since this was mentioned, I've tried this with a screwdriver and it works terrifically well, my old Land Rover makes some very odd noises though, but seems to work fine, so I'll leave it alone.

Sylvain,
Possibly one or both cams have too much end-float.
The cam followers (Tappets)are rotated by cams, the reaction to this is the cams tend to be pushed in and out as the valve springs are loaded and un-loaded.
On an early Matchless the magneto drive camshaft (inlet) is easy to check by pushing and pulling.
If you find your inlet cam has excessive end-float and produces an audible "clunk" you can prove it to be the source of your problem:
Find a piece of metal tube of appropriate dimensions (must slip over exposed spindle and OD must be smaller than bush)
Use a hammer and gently drive the outer cam bush inwards to reduce end float.

I have found that minimal end float is quietest.

Shims can be used if greater than 10 thou is required (in this application, thinner shims tend to break up.

On a fully assembled motor, the simplest method of checking exhaust cam end-float is to measure both cams across spindle thrusts, drift out the cover plug at exh bush, temporarily assemble with inlet cam in exhaust position and work out what thickness shims you need, or put cams back correctly and drift the exhaust bush as well. After you have tested, don't forget to refit exh plug (put some sealant on it)

In many applications, modern gaskets are a common cause of excessive end- float.

Good Luck!

email (option): n.gentner@bigpond.com

Neales' on the ball, cam end float and a new timing pinion makes a big difference.