Rock Guard, old vs new and the problem....


OneLapper

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I'm in the process of freshening up my bike. I installed a new rock guard on the subframe and noticed it didn't fit well. When the wheel is rolled backwards, the rock guard/flap hangs up on the tire.

A closer look identified that a production change happened and the rock guards available today do not fit correctly with the older fender liners. I recall seeing this issue at the NE24hr Challenge, maybe is was @privateer703 bike.

The original style rock guard was plastic. The new style is rubber. I didn't have time to modify it to make it fit.

Anyone out there that has the rock guard that hits the tire, this is why.
 

OneLapper

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Liquid has new subframe liners. Hope if fits your subframe.

That's where I got the new subframe liner and rock guards.

I've been holding off using new parts when I can. I had to modify my subframe to get the air bladder canister to fit, and the mod, albeit subtle, entailed using a heat gun to gain about 1/2" of additional clearance. It wasn't a pretty process.
 

Rashid510

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We did some part changes with the rock guard and the mudflap. (BTW @OneLapper your pictures are huuge)

Original rock guard had inserts where the mudflap would be installed. Mudflap was made out of plastic which had some issues rubbing on the swingarm.
Then we revved up the rock guard and mudflap with inserts on the mudflap and also a slightly different fitment with the rock guard (we had exactly the same issues when building the subframe on the line).

Technically all the "rubber" mudflaps should line up nicely to the swing arm. But if not you need to heat up the mudflap.
 

OneLapper

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Yeah, the iPhone doesn't allow me to pick an upload resolution. Not a phone friendly photo, sorry.
 

privateer703

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Yes that was my bike, the rubber mud flap actually rubs on the tire and when you try and roll the bike backwards the mud flap would be dragged and flipped, adding resistance to rolling the bike. What I did was bend the mud flap so that it now sits on the swing arm as opposed to between the swing arm and tire. Because it's softer than the plastic version you can easily bend it up onto the swing arm away from the tire.
 

OneLapper

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Yes that was my bike, the rubber mud flap actually rubs on the tire and when you try and roll the bike backwards the mud flap would be dragged and flipped, adding resistance to rolling the bike. What I did was bend the mud flap so that it now sits on the swing arm as opposed to between the swing arm and tire. Because it's softer than the plastic version you can easily bend it up onto the swing arm away from the tire.

I bet you have the same version fender liner as on my bike.

When I attached the rubbery rock guard to the liner, it doesn't sit right, and rubs the tire.

I'm sure it wouldn't take much to fix it.
 

Funk

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Rashid510 is correct, the only difference between the old mudflap and the new one is the softer material, the area around the bolt holes does not change the fitment when you use the OEM inserts. The old plastic ones would actually wear down the swingarm when dirt/sand got between it and the mudflap, hence the change of material.

The same mold was used for the old and new mudflap but because of the different material the resting position of the mudflap changed to stick out from the swingarm. To fix this in the short term we used a heat gun to reshape them, it wasn't 100% effective but from the testing I did it would work for most scenarios.

Bend the mudflap so it is resting on top of the swingarm, take a heat gun and heat the mudflap in a straight line across from the left to the right with the heat fun roughly 3in away from the mud flap. Make sure not to get to close or stay in one spot to long or the plastic will start to melt and you will get shiny spots on the mudflap, it will stick work, just won't look as good. If I remember correctly for the best results you want to heat a horizontal section of the mudflap to 80C-90C. Then let the mudflap rest until it is room temperature, at this point the mudflap will have some spring force into the swingarm keeping it away from the tire.
 

OneLapper

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Hey @Funk! Don't know who you are, but welcome! Sounds like you worked with Alta, great to have you here!

I agree with your suggestion to use a heat gun to coerce the flap into agreement. Not hard to do.

But, there are differences in the mold, at least for the early MXs vs the 2018 MX/MXR. The 2017 fender liner and plastic flap are physically different than the 2018. it's not that big a deal, I think that I can easily modify the new rubber flap to work with the older 2017 liner. Again, not much of an issue.
 

Funk

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Indeed I did. I worked closely with @Rashid510

Sorry @OneLapper you are correct about the molds being difference, I should rephrase. There are some details that changed in the mold of the mudflap (like the bosses by the bolt holes) but the overall shape/arc of the mudflap didn't change between the old and new.

It is possible there were some more significant changes that I am unaware of because I was not involved with the design change and only dealt with it on the production line as a MFG Engineer.
 

Philip

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Don't listen to him, he's Canadian!!


Oh shit, I am too now...
Does Canada grant citizenships to all EV tech specialists? If so, then the AOF membership should make all of us automatically eligible too. I don't mind getting free healthcare. What are the other benefits besides Canadian bacon, maple syrup, and Molson beer?
 

Redwolf

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Does Canada grant citizenships to all EV tech specialists? If so, then the AOF membership should make all of us automatically eligible too. I don't mind getting free healthcare. What are the other benefits besides Canadian bacon, maple syrup, and Molson beer?
Snow, I believe citizenship comes with all the snow you can take.
 

C5tor

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Don't believe the hype. No snow yet around Vancouver. I'm still wearing shorts every day. 😁
For true canucks and other denizens of northern climes, there is nor real correlation between the presence of snow and the wearing of shorts. It could be 20 below and you might still have shorts on. You might be wearing long underwear and snow-boots though.
 

F451

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Working on my dual citizenship as we speak eh.

Let me know if your EV firms up there need any tech writing, editing, training course dev. If so, I’m your man, even have digs I can stay in in Van if on-site work is needed. :)
 

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