Hi, I recently broke both the initial and the secondary kick start gears. After replacing both gears ok, the bike is now knocking I've removed all the clutch and basket and cannot see anything obvious? There is a few minor marks on the teeth of the big basket gear but nothing that could cause the noise I would of thought anyway.

Not sure what else it could be? Any help would be appreciated....

Hi

Is it a constant knocking or only at tickover? if it is only at tickover it may be the same problem as my 4T Evo where the de-compressor weight return spring had failed.

Seems to be worse at tick over but I'd have to have another listen, didn't want to run it too long. When the kick start went, I tried bump starting it a few times. Wonder if I've done any damage doing this?

Can you explain a little more on the de-compressor spring? Apologies for my limited knowledge, only had the bike a few months.

Seems to be worse at tick over but I'd have to have another listen, didn't want to run it too long. When the kick start went, I tried bump starting it a few times. Wonder if I've done any damage doing this?

Can you explain a little more on the de-compressor spring? Apologies for my limited knowledge, only had the bike a few months.

what actually caused this problem ,you usually dont need to jump on the kickstart a good steady push down is often enough

On the cam shaft there is a weight that when at tickover opens one of the valves to reduce the compression (to aid starting etc.) then once the rev's increase centrifugal force throws it outwards and closes the valve. At tickover a small spring keeps the weight in thus holding open the valve. Mine went and it was a horendous knocking noise that when the throttle opened went away.

If you do a google search for "beta evo 4t engine manual" and look for a pdf link from American Beta. download this file its the entire engine re-build manual. Look on page 67 the items are 4 & 5 that went wrong with mine.

Not saying this is your problem but it may help.

I can't get a link to it on here but if you are struggling I can email it to you.

If you do a google search for "beta evo 4t engine manual" and look for a pdf link from American Beta. download this file its the entire engine re-build manual. Look on page 67 the items are 4 & 5 that went wrong with mine.

I have to be honest, Its completely my fault it broke. Nether had a 4 banger before and I was jumping on it like a loon! I'm actually very impressed with the bike, especially the engine.

Ive found a few manuals but struggling to find the one your talking about? Can you email me: samrev3@talktalk.net

Secret with all 4Ts is find top dead centre and then one long push - never a kick! You'll shock load parts that can't take it. Good strong steady pressure is the way ahead.

Can't help you on the noise though sorry.

I would likely speculate that you may have picked up a bit of broken kickstart gear which got lodged in the primary gears(cramkshaft vs clutch clutch hub).

It does not take much of a distortion here to create a knock.

If the knock seems at crankshaft speed the crank gear is the likely culprit, the cam turns at half crank speed, so thus the frequency of the noise.

Cutch basket is much larger, thus the noise at prolly 3-4 times less crank speed.

No wish to tell you how to suck eggs, but is the knocking more of a clicky whirr?

.....if so it could just be the kickstart return stop is broken, loose, that's if it's similar to my Rev 3 250 2t.....just been there!

Bump starting won't damage the bike.... I did it for a couple of days and had no problems