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The 2-Stroke Garage => Turning Wrenches => Topic started by: KANDY on February 13, 2020, 10:40:09 PM

Title: Play in Clutch Primary Gear
Post by: KANDY on February 13, 2020, 10:40:09 PM
Hi All,
Please see the pic, could this play is allowed, it has almost 4mm play.
If no play allowed how to stop it. The part is from RD400 Daytona special.
Please advise.
Title: Re: Play in Clutch Primary Gear
Post by: Striker1423 on February 13, 2020, 11:01:40 PM
Play on the clutch baskets is really common on the RD. The rubber dampers inside the basket have probably been crushed.  You can drill the rivets, swap the rubbers and re-assemble by rivet, or you can tap the the basket and reinstall with countersunk bolts.

My 250, I did as described, but replaced it with a new billet banshee basket that came with everything to re-attach the basket to the primary gear.   
Title: Re: Play in Clutch Primary Gear
Post by: motodreams on February 14, 2020, 09:09:49 AM
Yes, very common like above poster said.  4mm is not bad really compared to many I have seen in running motorcycles.  Depending on how much you actually ride you can replace/repair or just use it as is.  Most of these bikes get what?  a couple hundred miles a year?  It will last years and is a relatively accessible part.
Title: Re: Play in Clutch Primary Gear
Post by: KANDY on February 14, 2020, 09:28:01 AM
I will be putting three M6 Countersunk Screws to arrest the movement. Hope it does not have any ill effect.
Title: Re: Play in Clutch Primary Gear
Post by: Barrie on February 14, 2020, 11:14:09 AM
Quote from: KANDY on February 14, 2020, 09:28:01 AM
I will be putting three M6 Countersunk Screws to arrest the movement. Hope it does not have any ill effect.
Really! I don't think that is the proper way of correcting the problem, yes drill out the rivets inspect and replace the rubber cush  drive inserts to minimise the movement
Title: Re: Play in Clutch Primary Gear
Post by: sav0r on February 14, 2020, 11:32:17 AM
Why would you drill and tap three holes when you could just drill and out the rivets, replace the rubbers, and then tap for m6? That makes no sense at all.
Title: Re: Play in Clutch Primary Gear
Post by: pdxjim on February 14, 2020, 12:07:31 PM
Just replacing the rivets with screws won't fix the problem.  Adding additional screws won't help either.

About 4mm movement is normal.  If there is more play than that, the rubber clutch cush bushings are probably worn. 

This is an LC clutch, but same concept.

(https://farm2.staticflickr.com/1907/31690457838_c6a60fceb8_k.jpg)

Pic stolen from Dusty350's massive thread here:

http://rdlccrazy.proboards.com/thread/45676/another-lc-engine-rebuild

Title: Re: Play in Clutch Primary Gear
Post by: KANDY on February 14, 2020, 12:13:35 PM
Quote from: pdxjim on February 14, 2020, 12:07:31 PM
Just replacing the rivets with screws won't fix the problem.  Adding additional screws won't help either.

About 4mm movement is normal.  If there is more play than that, the rubber clutch cush bushings are probably worn. 


Thanks for the picture and reply,
I will be taking out the rivets and see the condition of the Cush Bushings, will change it as advised.
Any one know the source of this Cush bushings. Could not find it in my googling.
Title: Re: Play in Clutch Primary Gear
Post by: pdxjim on February 14, 2020, 12:32:01 PM
https://yambits.co.uk/advanced_search_result.php?keywords=RD400F+1979+Clutch+Basket+Damper+Rubbers&search_in_description=1

https://yambits.co.uk/advanced_search_result.php?keywords=RD400F+1979+Clutch&search_in_description=1&x=0&y=0
Title: Re: Play in Clutch Primary Gear
Post by: 27 Cycles on February 14, 2020, 03:28:17 PM
Quote from: motodreams on February 14, 2020, 09:09:49 AM
Yes, very common like above poster said.  4mm is not bad really compared to many I have seen in running motorcycles.  Depending on how much you actually ride you can replace/repair or just use it as is.  Most of these bikes get what?  a couple hundred miles a year?  It will last years and is a relatively accessible part.

I just put my new clutch/old basket, together last weekend.  I had about the same amount of play and basically said this exact quote in my head..
Title: Re: Play in Clutch Primary Gear
Post by: SUPERTUNE on February 16, 2020, 12:56:24 AM
K,
4mm is fine for a street bike. If you want perfection as I do, for a high end build, replace them by drilling out the rivets, and using a Banshee kit to get new rubber dampners.
The hard part is the backing plate is real hard and will need a couple of brand new Cobalt drill bits to slightly enlarge the stock holes.
6mm X 1 button head or flat head screws will be needed and a 6X1 tap.
Go here for the new rubber bushings.

https://www.ebay.com/itm/Yamaha-Banshee-clutch-basket-cushion-bushings-SET-OF-8-for-OEM-basket-/312856804610?hash=item48d7b7fd02 (https://www.ebay.com/itm/Yamaha-Banshee-clutch-basket-cushion-bushings-SET-OF-8-for-OEM-basket-/312856804610?hash=item48d7b7fd02)

Chuck