[c0rpsejockey]

Have an issue with a brand new db release 29 I got this week. Drive side crank hits the chainstay under heavy pedaling. Have about 15mm clearance on non drive side, but only 5 or 6mm on drive side. I have a release 2 as well to compare it to - crank clearance is equal on both sides. Crank arm doesn't appear bent and bb is properly installed with single drive side spacer. I used string and tape measure to check frame alignment and seems ok. Q factor seem correct and centered on the frame. Compared to release 2, only thing that seams odd is chainstays dont have as much curve inward toward the wheels on the 29er. Seems to be 6 to 8mm wider from stay to stay than My release 2 right where the end of the cranks pass the chainstay. My understanding is this bike is a catch frame with 29" wheels. Hoping any catch owners could tell me how much space should be between chainstay and crank arm.
At this point, think I may have a bent or deformed rear triangle from the factory.
I have ticket opened with db and waiting to hear back.

 

[MUSTCLIME]

My 2016 catch has no spacers on the bb, I would guess bent crank(shipping) or wrong crank installed.... I think the 27.5 release had a different crank than the catch.... but I could be wrong.

 

[c0rpsejockey]

Cranks are identical on both bikes I have swapped them with exact same result.

 

[c0rpsejockey]

This is what I meant by less curve on the chainstay. The 29er in green.

 

[MUSTCLIME]

You are making contact with the chain stay with that gap? Do you have play in the pivots? How much movement do you have in the rear triangle?

 

[c0rpsejockey]

Yes, drive side crank hits chainstay only during very heavy pedaling. I cannot feel any play in the pivots from side to side. Hard to tell from one bike to the other, but the 29er kinda feels like frame is flexing a bit more just not sure.

Here is close up of gap

Compared to non drive side

 

[MUSTCLIME]

It really sounds like you are flexing the rear triangle, that is you are pulling it over to the crank arm.... and you are doing it on platform pedals....???? Have you checked the tightness of your rear quick release? Maybe pull off and replace the rear wheel to make sure the rear wheel seated well in the triangle, the axil is part of the strength of the swing arm....

 

[c0rpsejockey]

Its a through axle. To date, I have swapped the bb, cranks, axel, and wheel from my other release with the exact same results. I have also checked pivots for play and double checked everything with a torque wrench. I opened a warranty ticket last week with diamond back, but starting to get frustrated cause I have not heard back from them yet. I guess I could swap the triangles and pivots to see if the problem remains. Think that might tell me if the problem is with frame or triangle? Sorry if I ask dumb questions. Ive only been riding for a year and just started getting into wrenching on my own bike.

 

[Guy.Ford]

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[c0rpsejockey]

Live chat early this week asking for update... Got some story about system issues but she could see my ticket and they are working on it. I havent heard back. I have emailed customer service again asking for an update and a resolution. I had heard how much better db support has been the last few years. Not impressed. Think this is a symptom of the recent buy out?

 

[Guy.Ford]

...

 

[MUSTCLIME]

Here is a test, point the bike at a wall and put the front wheel against a wall. Then put a chair on ether side of the bike for balance... have a fat friend get on the bike, put the non drive side pebble forward and load the peddle. Watch the drive side crank arm and the swing arm clearance. My guess is you will see swing arm pulled to the crank arm with the chain in the 11 cog. This will mean you have a pivot or pivots out of spec.

 

[c0rpsejockey]

Here is a test, point the bike at a wall and put the front wheel against a wall. Then put a chair on ether side of the bike for balance... have a fat friend get on the bike, put the non drive side pebble forward and load the peddle. Watch the drive side crank arm and the swing arm clearance. My guess is you will see swing arm pulled to the crank arm with the chain in the 11 cog. This will mean you have a pivot or pivots out of spec.

I'll give it a shot thus evening. Thanks

 

[c0rpsejockey]

Used a manual trainer I made for my son. Looks like I get 1-2mm flex on the cranks and 2-3mm flex from rear triangle. Is this abnormal amount of flex? It's just enough to hit the drive side chainstay. Still curious if anyone with a release 29 or catch can tell me if their drive side crank arm is closer to chainstay than non drive side.

 

[MUSTCLIME]

The drive side crank should not see any load with platform peddles when it is near the swing arm, this is the up stroke. All the load is on the non drive side. I will say it again. I think you have a Release 27.5 crank set on a Catch frame. The catch frames have a wider rear swing arm for the wider tires. The SRAM gx crank that is on my 2016 catch has a 1/2 of a inch space between it and the swing arm. I have no spacers on my bottom bracket. What I think has happened is when your bike was being assembled, a Release 27.5 crank was put on your bike by accident. Release 27.5 cranks are not required to be as wide as the catch/release 29 cranks.

 

[MUSTCLIME]

Cranks are identical on both bikes I have swapped them with exact same result.

This is wrong, the catch swing are is wider and requires cranks with a wider Q factor.

 

[watermonkey]

I have a first generation Release 3 and 1st generation Catch 2. I will make whatever measurements I can and get back, but I'm pretty sure there's a difference in Q factor between the cranks on both these bikes. There's no question that the rear triangle is both wider and longer on the Catch. These bike came/are stock with different cranks - FYI.

 

[c0rpsejockey]

I have a first generation Release 3 and 1st generation Catch 2. I will make whatever measurements I can and get back, but I'm pretty sure there's a difference in Q factor between the cranks on both these bikes. There's no question that the rear triangle is both wider and longer on the Catch. These bike came/are stock with different cranks - FYI.

This may very well be the problem then. Bottom bracket and crank set are exact same part #'s on my release 2 and release 29 2, so both have exact same spacing, spindle length, q factor etc.

 

[watermonkey]

I did the best I could to measure the Q on both bikes. There's a chance my numbers are off, but I swear the Aeffect SL cranks on the Catch 2 are NARROWER than the Turbine cranks on the Release 3 by 2-3 mm. That being said, on my Catch 2, crank to chainstay clearance measured with calipers reads:
drive side = 8.2 mm
NDS = 12.7 mm

So, whatever the hell is going on, my Catch is sporting more clearance DS and less on the NDS than yours.

 

[c0rpsejockey]

I did the best I could to measure the Q on both bikes. There's a chance my numbers are off, but I swear the Aeffect SL cranks on the Catch 2 are NARROWER than the Turbine cranks on the Release 3 by 2-3 mm. That being said, on my Catch 2, crank to chainstay clearance measured with calipers reads:
drive side = 8.2 mm
NDS = 12.7 mm

So, whatever the hell is going on, my Catch is sporting more clearance DS and less on the NDS than yours.

Super appreciate you checking. Still waiting on db to get back to me. As a last resort, I am considering swapping rear triangles between the bikes to confirm if it's the frame or the rear triangle that's bent