[TCoop924]

I've having a bit of trouble getting my front 8" Avid Mechanical to mount properly. I've got it mounted to a 2002 Marzocchi Jr. T (regular dropouts). The adapter is rubbing against the rotor. The part of the adapter where the screws go bulges out on the side close to the adapter and the bulge is contacting the rotor pretty much preventing spinning of the wheel.

Any ideas on what's causing this and/or how to fix it?

 

[ghostrider]

Your description of the problem is a bit confusing, but I know that the word "Avid" is supposed to be facing out on the adapter. Other than that, bust out with the hammer and make some adjustments.

 

[TCoop924]

Yeah, sorry about the confusion...it's kinda hard to describe without seeing exactly what I'm talking about or knowing exactly what the adapter looks like. Anyways, I'll try and get a pict. up here soon if I can find a digi. cam to take one with.

 

[TCoop924]

By the way, I tried putting the caliper on with the adapter situated so that the "Avid" was on the outside, but that makes it so the caliper is situated incorrectly and won't allow the wheel to be seated properly since the rotor is pushed as far back in the caliper as possible. Bah!

 

[VTinCT]

Originally posted by TCoop924
By the way, I tried putting the caliper on with the adapter situated so that the "Avid" was on the outside, but that makes it so the caliper is situated incorrectly and won't allow the wheel to be seated properly since the rotor is pushed as far back in the caliper as possible. Bah!

Is this the factory mounting kit? The Avid adaptors are usually a snap to set up.

 

[sub6]

The problem is that you're using an adapter designed for QR20 or other 20mm forks, which are wider. There is no adapter designed to put 8" discs on a QR fork. You can either:

1 - machine 4 or 5mm off one side of the adapter (I can't remember which side but this HAS been posted before, probably in the DH forum).

2 - get the adapter for a RS Psylo Tullio (20mm) fork. That is supposed to have the regular spacing on the disc mounts (I'm not sure, just going by what I've read on here). Hayes definitely makes one; you may have to jury-rig a little......

3 - use a 6" IS Avid adapter, in conjunction with an 8" REAR I.S. NON-Avid adapter - like you would use to mount an 8" XT in the rear. The GRC adapter would work well, or the Shimano one.

This all stems from the general unwillingness of manufacturers to support 8" on QR forks. You will have to ghetto-engineer something, no matter what......

 

[ghostrider]

Weird, I'm running an 8" rotor on 99 Z1 QR fork. Bought the 8" adaptor, replace the 6" adaptor previously installed and voila, up and running with an 8" rotor. I can snap a pic if it will help - I had no problems at all getting this going...

 

[TCoop924]

Yeah, that would totally be helpful if you could snap a pict. of your set up ghostrider....Also, I checked Avid's site and found a .pdf with all the compatibility info....and I quote, "Avid's larger rotor sizes (185mm and 203mm) are compatible with Marzocchi forks with standard quick-release drop-outs but require an additional caliper mounting bracket. Avid offers these brackets and they are available through your LBS.
Note: Avid does not currently offer a bracket for forks with QR20 or QR20 Plus thru-axles." endquote

So, what's up with this? Do I need to go get a different adapter (though mine already has the 8" front adapter from what I thought)??

 

[sub6]

whoa, I didn't know Avid did that. Hayes is the opposite; they have a QR20 but no QR.

this is getting pretty wierd....

 

[Phatswalla]

Try calling or emailing Avid. They should be able to help you out.

(303) 762-9353
tech@avidbike.com


edit: Sounds like you just need a special Marzocchi 8" QR adapter or something. Avid should be able to clear it up for you. You probably just stop by a bike shop and ask them.

 

[TCoop924]

I already did...they thought I had a hub spacing issue...I haven't replied back, but I think that's BS since I've got Shimano XT disc hubs...they should work, right???

 

[TCoop924]

Well, I just e-mailed Avid concerning the problem (one more time), specifically if I need to go get a particular adapter or what have you....I'll post what I find out later.

 

[ghostrider]

Some pics:

 

[ghostrider]

1

 

[ghostrider]

2 - Looks like the Avid engraving is to the INSIDE on my bike. Whatever works, apparently.

 

[ghostrider]

Lemme know if you want so see a few more.

 

[TCoop924]

Thanks for the picts....one question...that adapter you're using...is it from Avid? It doesn't resemble my adapter at all. Mines pretty rounded...that looks more square...maybe it's just a different year design or something?

 

[ghostrider]

I got it from Speedgoat - it does say Avid on it. I'm guessing you've found your problem...

 

[TCoop924]

Sweet...I'll take a look at Speedgoat as well as my LBS and see if that's what I need.

 

[TCoop924]

Hey ghostrider...do you happen to know what year your avids are? Also, from Speedgoat, you just got the 10 buck mounting adapter right (see link below)?

SpeedGoat Bike - Avid adapter

 

[ghostrider]

I think my Avids are 03, but I'm pretty sure the adapter is for any year - it just uses different shims for different years. I think the Speedgoat link that you included is the correct item, although they charged my $15 for mine.

 

[TCoop924]

Ok, well, after talking with a lot of people. it just sounds like the problem is that the adapter is just misaligned (due to fork dropouts or something else). So, I just decided to file off about 1/32" from the adapter knubs so as to stop it from rubbing against the rotor. Brakes are both on and work great!