SM vs MXR (Rear fender & subframe)


aremean79

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Are they the same or is there any difference between the SM and MXR subframe and rear fender.

Thanks for the input
 

Jayfox911

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The mxr rear shock will not direct bolt on to the sm. You have to cut the subframe because the top of the shock will hit the subframe. I believe the frame is different.

the subframe and rear fender seemed like it was the same but the shock mount was different on the sm compared to the mxr.
 

Rashid510

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The mxr rear shock will not direct bolt on to the sm. You have to cut the subframe because the top of the shock will hit the subframe. I believe the frame is different.

the subframe and rear fender seemed like it was the same but the shock mount was different on the sm compared to the mxr.

Did you mean the rear bulkhead? An SM rear bulkhead and a MXR rear bulkhead are different, there are machining features in the casting which allow the rear shock to clear.


Are they the same or is there any difference between the SM and MXR subframe and rear fender.

Thanks for the input

The rear plastic subframe are similar on the SM and MXR. As the SM was built earlier than the R bikes, it was a different p/n, but rolled into the newer version. The SM rear fender does have screw inserts to install the rear tail light kit. The MXR technically shouldnt.
 

Jayfox911

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I just released I didn’t really answer your question. The entire rear tails section/subframe can be swapped between sm and mxr. The mxr just will not have the lights or bolts to hold the lights.



I tried to put a mxR shock on the older bike (sm,rx,MX frame) Picture of a mxr subframe I cut to put on the sm with a mxr shock. The top of the shock hit the subframe.
I believe the shock was stock rev 1 mxr that I used. Shock Fit perfect on a stock mxr.

the mxr subframe and Sm shock bolted up fine to the sm frame.

D5688C20-3D14-4838-B57D-0675AB9F372E.jpeg

F8D18CCF-1789-4A9E-BC6B-1A5DC5859AC7.jpeg
 

aremean79

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So just to be sure, is it safe to say that the red SM subframe will fit my MXR without any issues?

But I will need the SM rear fender because the bolt patterns are different?
 

snydes

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So just to be sure, is it safe to say that the red SM subframe will fit my MXR without any issues?

But I will need the SM rear fender because the bolt patterns are different?

Rashid510 will confirm, but I believe the answer to that is yes, the SM subframe will fit an MXR without issue, and will not require a different rear fender.
 

2018SM

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Please excuse me for going off subject a bit but since we are taking about going from Mx to SM, I had a question about SM to Mx.
The front brake rotor is way bigger than the off road version. Other than gettitn new forks, is there a larger rotor conversion for the off road wheel? My plan would be to just put a bigger front rotor on the wheel to use the extended and larger calipers on the SM forks?
 

Jayfox911

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Please excuse me for going off subject a bit but since we are taking about going from Mx to SM, I had a question about SM to Mx.
The front brake rotor is way bigger than the off road version. Other than gettitn new forks, is there a larger rotor conversion for the off road wheel? My plan would be to just put a bigger front rotor on the wheel to use the extended and larger calipers on the SM forks?
The Sm caliper uses a different bolt pattern, I would suggest you buy a complete stock exr or mxr front brake setup.

The lower fork lugs are different in a few ways; large axel vs small axle and the Sm caliper bots towards the fork leg and the mxr/exr caliper bolts perpendicular to the fork leg.
 

aremean79

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The Sm caliper uses a different bolt pattern, I would suggest you buy a complete stock exr or mxr front brake setup.

The lower fork lugs are different in a few ways; large axel vs small axle and the Sm caliper bots towards the fork leg and the mxr/exr caliper bolts perpendicular to the fork leg.

For the caliper, you can just buy the extension bracket to make the MXR/EXR oem brakes fit the bigger diameter SM rotor.

If you are looking to use the SM brake caliper (radial mount) onto the MXR/EXR fork, I believe the radial mount adapter can be used (see picture attached).

One thing though... can someone confirm that the front axle size is not the same for the mxr/exr and the SM? I didnt know about this.

20200422_164535.jpg

ktm_supermoto_320mm_brembo_100mm_axial_to_radial_1553604690_e6e328ff_progressive.jpg
 

2018SM

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That looks like a great hack for the Mx to SM brakes. For me to go from SM to MX front it sounds like I need new forks and brakes then yes? And of course a wheel.
Also, I believe the KTM Air forks fit right on but am not sure which years the caliper would bolt up. Any ideas?
 

2018SM

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Good morning Armean79. I can confirm the Mx wheel axel is smaller than the SM. The only way to go from SM to MX is to get entire front end. The KTM air forks are a nice fit. Thanks again for all the help.
 

aremean79

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Good morning Armean79. I can confirm the Mx wheel axel is smaller than the SM. The only way to go from SM to MX is to get entire front end. The KTM air forks are a nice fit. Thanks again for all the help.
Thanks... But Im actually going from MXR to SM. Rashid told me that I will need a spacer in order to reuse the smaller, original, MXR front axle on the SM front wheel
 

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