2019 EC300 Engine Vibration

[Doc Brown]

Coming from a 300 KTM with counter balancer I was quite spoiled.

First GG I have ridden was my mates GP300/18. Its vibrations were horrible, much more than any of the older 300 KTM's I had owned. But, during riding I didnt feel them in the bars, a bit in the pegs though.

Second GG was my own GP300/18 and its vibrations were bad too, a tad better than my mates bike. His, when parked on the side stand vibrates so bad that you can see the front wheel vibrating. Its like it is jumping up and down a quarter of an inch. That was a bit, not much though, better on mine.

At the moment I have a EC300/19 and it also vibrates a lot, worse than my 2018 but better than my mates 2018. Its a bit too much in my opinion but on neither bike I did feel vibes coming through the bars while riding...

[RudolfHucker]

Riding today has shown that a lot of the vibration has been absorbed by the changes I have made.

However, the vibration levels are still higher than my pal's EC300 and we bought the bikes together from the same dealer. Vibration through the seat is unaffected and is massive. Also, with the bike on a stand with the wheels off the ground, the front wheel will rotate with the engine ticking over. Fuel in the tank will dance about and form waves 3-5 cm high.

Clearly, this level of vibration is not sustainable as it is bound to cause damage to the bike and decoupling the bars and pegs is only masking the effects rather than fixing the source. Riding at road speeds produces too much vibration for the countermeasures to cope with causing hand numbness and cramping.

Time to get the dealer involved and start stripping down likely problem areas like the flywheel and clutch.

[Davehuge]

I hope your dealer will be understanding and help resolve this vibration issue. I guess it'll be tricky as it's not something that can be easily measured, just make a comparison to other bikes as you've already done.

Assuming the main bearings are good, my guess is the cause of the vibration is the crank. Ideally it would be great to drop in a new crank and see the difference.

Good luck and let us know how you get on.

All the best, Dave.

[GasGas]

Originally Posted by dzhitshard

Frankly, the 2018 shakes pretty horribly at the bars compared to all the other 2t austrian bikes I've had.
Both the bike I test rode and the one I bought so it wasn't just one.

I cleaned out quite a lot of it by replacing the grips with Emig2 grips.

I feel these stiff Renthal bars carry a lot of it straight to the upper body too. I am ready to replace them with some ProTaper EVO that I used to take some of the jarring out of my older KTMs & Husky but am holding off for now after I put on the Mako 360 mounts. Over the last 6 hours of frozen ground riding with the Mako 360 (IE, the ones always the harshest for me) I eliminated most of the joint pain I was getting from my shoulders, elbow, and wrists.

I had been a fan of the Mako 360 on my previous bikes so I broke down and put them on the GG. Man, I don't regret spending that money at all.

The cross bar on the Renthal bars can be removed and does soften them a noticeable amount. Renthal does advise they can be run with or without the cross bar.

[RudolfHucker]

Some excellent detective work by Mr Quick has revealed that there has been a dodgy batch of crank end nuts on the clutch side and these are coming loose. The UK importer has seen a few already.

Hopefully, replacements will arrive tomorrow in the post and I shall be taking the clutch case off to check if this is the issue.

Part number at fault is : ME250032018 - Crankshaft Pinion Locking Nut

[RudolfHucker]

Stripped both sides of the engine today and found nothing unusual at all.

Everything is solid. There is a torque paint mark across the crank nut and shaft and it hasn't moved. Clutch, flywheel etc the same.

Have slackened and re-torqued the engine mounts and am now sat scratching my head. I shall rebuild and see if anything has changed. Can't say I am expecting anything dramatic.

[Gasser Nate]

My flywheel nut was loctited but not tight against the flywheel, I was getting a clunk when on and off the throttle. Might be worthwhile removing the bolts and torquing to spec. Another thing is I don?t think gassy spec on crank truing is the best. I have rebuilt a couple and trued them properly and the owner has been amazed at the difference. Bit hard to check in the motor though!

[RudolfHucker]

I think it's boiling down to either the crank being out of balance, a badly cast piston or small end bearing fault.

I'm not going to split the cases, it will go back together and the dealer can sort it out under warranty.

[Gibnut]

Originally Posted by Gasser Nate

My flywheel nut was loctited but not tight against the flywheel, I was getting a clunk when on and off the throttle. Might be worthwhile removing the bolts and torquing to spec. Another thing is I don?t think gassy spec on crank truing is the best. I have rebuilt a couple and trued them properly and the owner has been amazed at the difference. Bit hard to check in the motor though!

Had the pleasure of riding my brother?s ?13 EC300 - Nate had trued the crank & rebuilt it previously. Smooth as butter and very, very strong motor, bottom to top.

Crucially, less vibes, too..

[Zimmo]

Originally Posted by Gasser Nate

My flywheel nut was loctited but not tight against the flywheel, I was getting a clunk when on and off the throttle. Might be worthwhile removing the bolts and torquing to spec. Another thing is I don?t think gassy spec on crank truing is the best. I have rebuilt a couple and trued them properly and the owner has been amazed at the difference. Bit hard to check in the motor though!

My 2019 EC300 flywheel nut was not tight or locktited.

Eventually it unwound completely towelling up the flywheel, ignition, bendix and cover. There was no discernible difference in vibration ... until it eventually stopped with a lack of spark