Noisy cam pinions

[BarrieSteel]

Thanks for the removal methods Roger, seen on the forum removal one method engineers hammer and vice,thought a bit crude that one without damage, tube over cam looks the best way. Barrie

[BarrieSteel]

Hi I was fortunate that a club member contacted me having a new pair of pinions from club spares a while back surplus to requirements, fitted ok, a lot quieter than before,there is some backlash in pinions though? Hope all ok now.

[nevhunter]

With no backlash they WILL WHINE but as the motor warms the lash will increase as the alloy case expands more. There's no way to adjust them other than make a new set. Doesn't have to be both Gears Try to have NO run out on the crankshaft pinion shaft. IF the gears come from a different maker the Teeth Pressure angle may not be a matching situation.. Before about 1930 the teeth were coarser and GROUND to final size like the SQ4s are in the drive. Coupling. Older sets will swap . The Bigger sectioned gears should last longer but I doubt anyone makes them when the Later ones are available freely Nev

[simon.holyfield]

Hi Barrie,

I've just seen the video you pm'd to me. Are they as noisy with the outer bearing fitted?

Perhaps post the video and see what others think?

[nevhunter]

Vids with sound always seem to magnify whirring and tapping noises in Machinery. Nev

[BarrieSteel]

With outer cover on is just the same new bushes fitted all good there, just little concerned is backlash to great,meshing of teeth seem a bit shallow.Has anyone else had same thing on new pinions fitted, being repro pinions from club spares ,member had while back.No ploblem at this stage to do what Paul say try old ones in reverse trial and error I suppose ,thought on this one would be great Barrie see clip.

[nevhunter]

I couldn't access that . I just tried twice. It will be my computer..
It's not likely to fail but if you WANT it right get it right as it will Probably worry you.. Measure the pinion teeth depth with suitable small rollers IN the teeth, opposite each other allowing you to use a micrometer and COMPARE with a good one. Don't be pulling the pinion on and off.. Some out there are also not hard enough and wear rapidly. I've used either original old stock, or had them made very accurately and Matching each other for pressure angle. The timing marks can be out also.The desired fit is virtually NO backlash. Play there makes things wear faster and if it's case hardened you MAY go throughthe case This isn't rocket science but our bikes are not NEW either. Those gears take a highload.. I'm not very mobile at the moment but I'll try to have a look at a few cases with cams and flywheels in. Keep in touch. Nev

[nevhunter]

Having another look at what you have It appears as if the CAMSHAFT teeth may be a more modern profile and not matching the other. It's NOT meshing deep enough, also.. I don't think ARIEL ever changed after going to the finer teeth in the early 30's but many gear cutters don't carry the earlier tooling as there's not much call for it. The best made gears are generated and match perfectly and run quieter.. Somewhere in the factory notes there is a reference to going to the finer gears there and it was to have more silent running by making the noise go towards higher frequencies with more teeth
Maybe they were working on you being deaf in the higher frequencies, or may I dare to suggest, save the cost of finish grinding the gears as had been done up to that stage. But always done on the SQ4 coupling gears or you would be heard a couple of streets away. Nev.