Compatibility - Mega-9 and old cranks

montair

Retro Guru
Compatibility issue, I have;
95 Orange P7 frame
Front mech (32.8mm) Deore LX
Rear mech Deore LX.
Shifters Deore LX all the above Mega 9.
Cassette is a 9 speed.
Crank Deore FC MT60 on a 113mm BB.

I can’t get the front mech to not hit the chain on the smallest ring / top 2 on the cassette, the chain line looks fine
The low stop adjuster is adjusted all the way in so the cage can go no further without manipulation. Then when you try to go to the middle ring it jumps straight to the top.

Questions
Is the crank not compatible with mega 9 and I need a newer crank / BB setup ?
Is this the BB to small ?
Should Janice really marry John if she still yearns for Dave?

If I need a new crank set up the FC MT60 is surplus to requirements
 
space the BB out 2mm on the drive side with a shim, there should be enough axle length to still fit the non drive side.
 
But will that stop the jumping( granny to big) its like the pull is too big and a mega 9 crank ring to ring gap is bigger ??? ( If that makes sense?)
 
@Tootyred and @novocaine Thanks for the info i have a handful of spacers ( from god knows where or why). I will see if i can set the crank side to 61 from 56.5. Hopefully this will work. If it does then i can go get a new 122mm BB
 
I’d try the new BB, but a word of caution, sometimes the 9 speed low-band front mechs don’t work well with earlier chain sets. I don’t know why…
 
If it's of any use I have a mega 9 Deore square taper crankset I was going to list on Facebook later. Came on my Haro Extreme but is far too modern for that so I wont be using it. Yours for a tenner plus postage if it helps you out. Let me know if its of interest and I can always pop up a couple of pictures for you.
 
Here you go. Arms are 175mm. I took them off a few days ago in preparation for sorting out my Haro, it should be all M900 on there. I guess these may have been cheaper for the previous owner than just buying new rings if they had worn the originals out. Threads and tapers all seem good.
 

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She should marry John for the security and continue an affair with Dave.

I would use a high clamp front mech, never got on with low clamps.
 
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