Front cush sprocket thingy..

[fewtrees]

Simple question...

Is it really necessary to have this, I'm replacing the front and rear sprocket and wonder if the original front is mandatory or could I use a renthal sprocket instead?

[Maverick]

I think not to tempt the angry gods of gearbox shaft bearings rather stick with the original. Have seen and heard what a non standard sprocket did on Lootch's bike and it wasn't pretty. Fortunenately he got away with no damage but think any longer and he would of run into major issues.

[mal]

Hi Fewtrees,the sprocket obviously has the cush drive for a reason,i think i would always replace it with a genuine replacement.

[chronyx]

What's a cush drive?

[YEN_POWELL]

The only time mine had a Honda front sprocket was when it was new and it also had the sad excuse of a chain that Honda supply as original equipment (and that didn't last very long compared to the DID replacements that came after). Never had a problem with Renthal front sprockets.

[BobA]

Don't even consider a front sprocket without the rubber wheels (I think cush drive is a confusing term)

For the sake of £20 (David Silver) for the original, the chances are the cheapo one will be fitted the wrong way round (I have seen two examples of this) and this immediately puts the whole drive/sprocket assembly out of line. In time, this chews away at the gearbox output shaft, and once this has done its nasty work of breaking down the case hardening on the shaft, failure is just a matter of time.

Assuming the worse happens, and you've got a great engine, the only option is to take the engine out, split the cases, and replace the output shaft. If the engine is pants, you will be wanting a new one.

Hopefully, you are now in no doubt what to do!

Bob (Scarey bloke of Sussex!!)

[Lord Stig]

I've never used one. 83,000 miles and no problems. I agree with Yen about the rubbish OE chain too...

Stig

[Dilbert]

Stig and Yen are probably right about it being Ok without and Renthal is a pretty good make i believe, but i have to agree with Bob and especially if you want to go off-tarmac when you will get more jerky forces transmitted, is it really worth it for £20, some engineer has spent ages deciding to put the rubber mount there, he must have done it for a reason! and no it's not called a "cush drive" that is quite specific to the rear sprocket mount/ drive

[iswoolley]

Do Renthal now make steel sprockets?

In the past they tended to make alloy sprockets for mx racers, which lasted about the duration of one race (or one trip to the shops!). Not the longevity you look for with a road bike.

[YEN_POWELL]

Do Renthal now make steel sprockets?

In the past they tended to make alloy sprockets for mx racers, which lasted about the duration of one race (or one trip to the shops!). Not the longevity you look for with a road bike.

Yes they do make steel sprockets. Alloy sprockets are pants for road use.