Rubber donut replacement??

[mhibbs]

I just bought a Merlyn 11a and will be racing it for the first time very soon. I'm wondering if I need to replace my donuts immediately. I see some metal beginning to show through the rubber but it's in a spot where the rubber appears to be very thin to begin w/, so I'm not sure if it is really a structural concern. I'd like to be able to make it through the first race weekend as is b/c i don't have a lot of time to change them out between now and then, but I also of course don't want to blow one knowing that's definitely not a good situation. Picture attached...

Thanks guys

[Brian]

They look pretty good to me. I look for cracking in the rubber near the plates, and between the plates. That one looks almost new. When new they have a strap around them where the rubber is abraded on yours, and I use a long hose clamp to compress them when I have to take them off. Both tend to damage the rubber on the outside a bit.

Brian

[DanW]

Congrats on your new Merlyn.

Brian is right on the money with the appearance on the outside of the plates and inspection for cracking.

Two things to add from someone who has experienced donut failure:

Make sure all the bolts are torqued properly. They will work loose. Donut failures have been blamed on the rubber, but later found to be due to loose fasteners or incorrect grip length.

Make sure the bolts are the right grip length so there are no shearing drive loads on the threads.

Regards,
Dan Wise

[mhibbs]

Congrats on your new Merlyn.

Make sure all the bolts are torqued properly. They will work loose. Donut failures have been blamed on the rubber, but later found to be due to loose fasteners or incorrect grip length.

Make sure the bolts are the right grip length so there are no shearing drive loads on the threads.

Regards,
Dan Wise

What is the correct torque spec?

Thanks!

[DanW]

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