Linkage Issues EC 300 '18 and '19
 

On all my Gassers the linkage bearings were toast after only a few hours, so that seems to be an issue.

GP 300 2018: 54 hours
EC 300 2019: 36 hours -replaced- defective again at 71 hours
EC 300 2019: 22 hours

On my second 2019 I felt play after only 3 hours getting worse, now that it has 30 hours when I pull up the wheel it is about 5 mm (0,20 inches).

I once replaced the bearings with OEM parts just to learn that after another 35 hours they where toast again. Obviously the bushings are made of cheese. Considering that the kit costs USD 166.- over here I was not amused.

I now ordered an All Balls Kit which is considerably cheaper (USD 107.-) but I have heard so many different statements about the brand that I am a bit anxious. Some say AB parts are crap others say they used them w/o problems.

I'd be interested in your opinion....

Thanks, Doc

(cross posted to TT)

i plan on adjusting the play with a better quality bushing made to fit better/the least play possible, in case the bearings are still in good shape.
the more play, the more everything gets hammered. so no play+ grease and a harder bushing should last longer.
or maybe you're pressure washing that grease out of the bushings or riding alot of deep mud or crossing waters?

I replaced the linkage bearings on my GP300 at 70 hours & thought that had I regreased sooner they might have lasted longer.
After 100 hours I noticed some slack at the shock at the topping out point when I lifted the back of the bike. Pulled down the linkage bearings again to find they were OK.
I ended up replacing the lower shock eye bearing & even though the old one looked OK there is no longer any slack in the shock.
Might be worth a look, you can buy them as a Yamaha part in a kit with the lower bush, bearing & seals.

Cool hint! Much appreciated. In the AllBalls Kit I ordered the lower shock bushing/bearing is contained. Now that I read this I get an idea of what could be wrong. Before the first ride I could feel play already so I disassembled linkage/rocker arm and re-greased with high quality water proof marine grease and still had this play. Though I haven't ridden it more than twice up and down the road. Maybe the lower shock bearing is/was the culprit.

I need to dig deeper into that as I did visually inspect the shock bearings on my second bike when I replaced the linkage bearings at 36 hours. But they looked ok and they also looked good when I replaced the bearings and bushings again after 71 hours. It never was free of play and I now get an idea what the reason could be.

Do you have the Yamaha P/N at hand? Or can you tell me from which Yamaha (model/year) the spares would fit please?

Now that I have read what ECRider wrote I am not so sure that the play comes from the linkage. But yes, better quality bushings would be great. Unfortunately I could not find anyone who was willing to machine some for me for a reasonable price. I found better aftermarket bearings from SKF and also the seals are available from SKF.

I found play on all 4 Gassers in my garage. I found play on my GP that did not get cured fully by replacing the linkage bearings. On my friends GP I found play after 80 hours and that was cured by replacing the rocker arm bearings, the one in the wishbone was ok.
On both my 300's I had play from day one. On the first one the play did not go fully away after replacing the bearings.

No, I use a pressure washer but it is a low pressure system from K?rcher and if I blow off dirt from the linkage I really take care not to get too close... That is not the reason. I suspect the shock... but we will see.

Doc,
from the Technical Touch website you can download the 2020 KYB catalogue & it has all the Gas Gas part no's so you can find cross-over parts from other bikes.
From the catalogue the Gas Gas lower shock bearing & bush is the same as on YZ250F/450F from 2014 -on so I got an All Balls kit, see link below.

https://www.mxstore.com.au/p/All-Bal...Bearin/29-5015

The kit looks to cover other model years as well, so maybe the part has been upgraded.
Even though I have a plastic linkage guard, this bearing cops a lot of abuse as its the lower shock/linkage is first to get hit when hitting logs.

ECRider you are a star! Many thanks. I already downloaded the TT/KYB Manual :) But having the All Balls P/N makes things a lot easier.

Yes, now that you mentioned it I checked pics of my bike and it seems the bearing of the shock gets the first and probably hardest hits. I use a thick AXP Racing bash plate with linkage protection but that sure does not reduce an impact much.

Thanks again!

Doc

No worries. I have the AXP bash plate with linkage guard as well & its OK apart from draining oil. ( I now drain oil by loosening the clutch cover, but you can't check/clean the magnetic sump plug this way).
Post up after your bearing install if it helped fix the problem.

:D


https://i.postimg.cc/3rffPfLg/20190825-121041-9920.jpg

I have a link guard too.
The linkage bearings
just don't seem to last. I even use the high dollar Jet Lube.