For me if a bolt is thread locked and you disturb it, the bond the thread lock is supposed to form has been broken. It will serve however to increase friction and any attempt to re-torque will therefore not be accurate. I would remove the bolt, clean off the dried thread lock, re-grease the shaft and re apply fresh thread lock..............tighten to correct torque and leave undisturbed for 24 hours.
Rail 9.7 chainring rubbing
- Thread starter dannypr
- Start date
Zekiel
New Member
Does the Mino link setting affect any of this as far as stay position is concerned?
Mr_Price
Active member
Mine was in low. I can’t really see that it would make a difference but I’m a noob.
I didn’t get enough rides in to try the high position. The 9.8XT they lent me in in high position and so far I’m really enjoying it.
Rafael Campos
New Member
Guys, just rode my third trail with my “almost” new 300 kms rail 9.8 and got the same scratch on the chainstay... have you came to any conclusion? Here in Brazil the fix will be touching up the scratches and “find out” what is happening... seems they are pretty lost...
Mr_Price
Active member
Still working on it is the short answer. Check your main axle pivot for tightness and any play.
I will continue to post updates as I get more information.
Rafael Campos
New Member
Right, tks.
Ive checked the torque on the main pivot and it was loose. The wrench moved half a turn to reach 30Nm. After torquing it, the chainstay remained alarmingly close to the chainring. And when a say close, I men less (much less) then a mm close. The motor seems to be firm on the frame and the most obvious bolts seemed correctly torqued. Very disappointed with the bike with such low mileage and such right price with such annoying problems.
Mr_Price
Active member
It does seem that certain configurations of this bike have the chain ring very close. I do wonder if the rub comes from the rear triangle flexing against the chain stay because the pivot axle is loose. If you managed half I turn, follow @Mikerb advice at the top of the page and set it properly, otherwise it will happen again and lead to more mess....
Rafael Campos
New Member
It is
It is pretty strange though... the flexing would occur, at least in theory, when you charge it. And when you do it and the rear shocks compresses, the clearance increases... the thing is close when there is no weight what so ever on the bike. Tomorrow it will go to my LBS, But i have to say that Im pretty pessimistic, since you guys are still dealing with the problem where the thing is manufactured...I’ll check the tread you mentioned. Keep us posted, please.
Rafael Campos
New Member
You will be between chainring rubbings and motor failures... How we use to say in Brazil, "if you run the beast catches you... if you stay the beast eats you".I'm waiting my Rail 7 still, but when i read these post i'm thinking should i cancel my order and start looking Turbo Levo instead...
The Specialized support seems to be unbeateble though... I´ll be towards Levo if I were you.
Zekiel
New Member
There’s plenty of good stories of Trek support so I wouldn’t let that sway you. Also keep in mind either issue isn’t fully known how extensively they occur. This thread only has those owners who have unfortunately experienced this problem. Get the bike and decide for yourself or, if the Levo suits you more, go for that. They are both great bikes and all bikes have issues of one sort or another.
Rafael Campos
New Member
Sure! Its a valid point. I'm not saying Trek after sales is bad (to be honest this is my first Trek), just reinforcing how strong Specialized's is (this I know from facts). But what amazes me the most is the fact that this must be a geometry problem... not rocket science. An eletric bike is not a very complex machine. The tread is form january...more then time for a proper reaction, in my point of view, at least. Specialized also took ages to solve their motor issue as well... not sure if they did, to be honest.
Mr_Price
Active member
I'm waiting my Rail 7 still, but when i read these post i'm thinking should i cancel my order and start looking Turbo Levo instead...
Ive seen over 10 different spec / size Rails, mine was the only one that had such small clearance. Small sample size I know but consider that AND I believe it’s only been carbon frames that’s been impacted by this. The 7 is alloy. ??????
So it happened that Rail is gonna be delayed.
I cancelled my order because there was one M-size 2021 Turbo Levo Comp at other LBS's storage at theirs other shop.
I'll get it next week, as soon as they have it at theirs shop here where i live.
I'm not sorry at all.
I cancelled my order because there was one M-size 2021 Turbo Levo Comp at other LBS's storage at theirs other shop.
I'll get it next week, as soon as they have it at theirs shop here where i live.
I'm not sorry at all.
Rafael Campos
New Member
No reason to be! Good luck with the new bike! Enjoy!
Had the same problem on my Trek rail 9.9, i found it catches when the suspension is extended. If you sit on your bike and look down you will see the chain ring has greater clearance from the swing arm, i think it catches through jumps, bad design, however it has only caught the invisiwrap on mine
Pool Hooligan
Member
I’m new to mountain biking and I had the same problem. On a trip out with my kids on a flat river bead, my chain snapped and the chainring rubbed the frame like all of the posts above. The problem was the large but had vibrated off and allowed the chainring to have about 1/8 inch play.
Rafael Campos
New Member
Hum... you are correct. When you sit, the clearance increases. But don’t count on that... i made the same observation and the thing rubbed even when seated on the bike, with the rear shock compressed...
Rafael Campos
New Member
Pool, didn’t quite get you... I’ve followed until the chainring rubbed the frame. After that you wrote something that seems to be the cause, but i couldn’t understand... can you explain?
Pool Hooligan
Member
im sorry. The large nut that holds the crank in place had vibrated off a few turns. This caused movement which caused the chain to snap and the chainring to rub against the bike frame.
Rafael Campos
New Member
Right. Tks... seems that your root cause is pretty obvious. Not my case.
I just scrolled true all of the forums to see if anyone has the same problem.
It seams i win.?
After 120 miles the ring came lose and broke my chain. Whent to my Trek dealer and they tightend the ring using loctite.
After 10 miles same problem.
Changed the chain. Again same problem.
Then chainged the front gear. And it worked.
Last week after 600 miles. It al started again.
Today got it back from the Trek dealer and guess what. 6 miles and my new chain is ready for the trash. So is my rear fork by now.
Any idea´s. Before i go crazy?
Thanks, Don
It seams i win.?
After 120 miles the ring came lose and broke my chain. Whent to my Trek dealer and they tightend the ring using loctite.
After 10 miles same problem.
Changed the chain. Again same problem.
Then chainged the front gear. And it worked.
Last week after 600 miles. It al started again.
Today got it back from the Trek dealer and guess what. 6 miles and my new chain is ready for the trash. So is my rear fork by now.
Any idea´s. Before i go crazy?
Thanks, Don
neiloxford
Member
Is there a lot of tension on the rear derailleur when you try to pull the derailleur forward ?
Can you take a picture of the whole drivetrain with the chain on the smallest cog at the back ?
Was the chain shortened ?
If it all looks ok, then I am out of ideas.
Last edited:
The chain was origianaly a 126L. Shortend by 2. The picture is after my ride when i needed to shorten it again with 2.
neiloxford
Member
Looks good to me on set up.
My guess is the KMC front chainring, but not sure as it is meant to be good for 3,500km
The black coating looks to be coming off in places, perhaps suggesting it is worn ? ( maybe the photos though )
it does appear that chainring goes with the kmc chain...
www.kmcchain.eu
www.kmcchain.eu
anybody else ?
My guess is the KMC front chainring, but not sure as it is meant to be good for 3,500km
The black coating looks to be coming off in places, perhaps suggesting it is worn ? ( maybe the photos though )
it does appear that chainring goes with the kmc chain...
Bosch Gen 4 Super Narrow | KMC Chain
Bosch Gen 4 Super Narrow chainline 52.0mm 34T Art.nr. BFCB45234 Art.nr. BFCB45234 Size: 1 2 X 11 128 Colour: Black Treatment: Hardened Chromoly steel For Bosch 4 Systems Direct Mount; 9,0mm offset Perfectly..
www.kmcchain.eu
3.500km : Lasts. And lasts.
3.500km+: Lasts. And lasts. The 3,500 KM + drive is the perfect solution for demanding drivers. The combination of our e1 EPT chain and our narrow sprockets enables a guaranteed mileage of 3,500 kilometres..
www.kmcchain.eu
anybody else ?
Last edited:
Rafael Campos
New Member
I feel i’m coming to a decision after reading your post. I’ll get rid of this f&#% bike. Mine is almost 2 weeks in my LBS, they’ve painted the scratches on the chain stay, they don’t have a clue of what is going on, just tightening randomly nuts and bolts.. this issue is posted here for almost 5 month and Trek doesn’t say a word to any of us so far. Bike shop owners / operators seems completely lost. This is an expensive bike and a very poor experience! What a lack of respect!
Thanks for your advice. Realy apreciate you guys thinking with me.Looks good to me on set up.
My guess is the KMC front chainring, but not sure as it is meant to be good for 3,500km
The black coating looks to be coming off in places, perhaps suggesting it is worn ? ( maybe the photos though )
it does appear that chainring goes with the kmc chain...
Bosch Gen 4 Super Narrow | KMC Chain
Bosch Gen 4 Super Narrow chainline 52.0mm 34T Art.nr. BFCB45234 Art.nr. BFCB45234 Size: 1 2 X 11 128 Colour: Black Treatment: Hardened Chromoly steel For Bosch 4 Systems Direct Mount; 9,0mm offset Perfectly..
3.500km : Lasts. And lasts.
3.500km+: Lasts. And lasts. The 3,500 KM + drive is the perfect solution for demanding drivers. The combination of our e1 EPT chain and our narrow sprockets enables a guaranteed mileage of 3,500 kilometres..
anybody else ?
Are you sure it´s a kmc chainring. Because i´m sure the chain and casette are shimano. Our doesn´t brand make a difference?
I realy hope you are wrong altough it´s starting to feel you are wright.
The guys in the shop do their best but as you say they don´t realy now whats going on.
I´ll keep you posted hope we can find the fun i our bikes again.
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