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Discussion Starter · #1 ·
So, with the help of a friend, I've basically completed my first bike build. Though, we're having issues with completely dialing in the drive train to shift smoothly.

I'm using a shimano XT bottom bracket and a XTR M960 rapid rise rear derailleur, along with XT trigger shifters (also a XT m770 front der).

Question 1 - for the spacers on the BB, which side do you put two spacers on and what side do you put the one spacer? I currently have two spacers on the crank side, and 1 spacer on the other. I ask this because if wrong, it could effect chain line and dialing in smooth shifting?

Question 2 - the rapid rise rear derailleur does not have a barrel adjuster at where the line meets the derailleur, is this normal for XTR rapidrise derailleurs? I ask this because most derailleurs I've used in the past had a barrel adjuster. We've just used the adjuster on the shifter instead but does this effect dialing in smooth shifting?

Question 3 - any tricks or tips to get the shifting dialed in on my rapidrise XTR shifter that I could use to help smooth out the shifting?

Thanks in advance.
 

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That's a nice build and should yield smooth shifting.

Q1 - You have it installed correctly. If it wasn't, the chain line would be off, and your front der. would not be able to reach the inner or outer ring (depending on how the spacers where misplaced).

Q2 - Perhaps the newer models don't have barrel adjusters. Using the one at the shifter should not affect your ability to get it dialed in.

Q3 - Check the der. hanger.
It might not hurt to try a different chain if you have another one.
If you need specific instruction on der. adjustment, check parktool, sheldon brown, and youtube.
 

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Crainius Maximus
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Q1 - What is your bottom bracket width? Its possible you have a 73mm BB, which would necessitate only one spacer on the drive side and none on the other side.

Q2 - rlouder is correct...fine tuning is now handled by the barrel adjuster at the shifter only

Q3 - Also make sure your B screw is adjusted properly. If the upper pulley on the rear derailleur is too far away from the cassette, your shifting performance is going to be poor.
 

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With the rapid rise RD start tuning with the cable at its slackest that means the RD is shifted onto the large sprocket on the RD...

Then work your way up the cluster (towards the smaller sprockets)...
 

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Discussion Starter · #5 ·
For the chain, I used a brand new XTR chain with a wipperman power link.

For the derailleur hanger, I also did not use that rear vertical screw that increases tension of the line, way in the back that moves the derailleur up and down, would this matter?

The bottom bracket width is 68mm.

Ah yes, the B-screw is the vertical screw that changes the angle of the derailleur? What is the best way to fiddle with this screw? I'll check to make sure that the upper pulley is as close as can be to the cassette with the B-screw adjustment.

thanks for the feedback guys
 

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Discussion Starter · #6 ·
*also in a side note, does anyone know the torque values for the rear shock mounting at the front and rear eyelet?
 

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darnelli said:
For the chain, I used a brand new XTR chain with a wipperman power link.

For the derailleur hanger, I also did not use that rear vertical screw that increases tension of the line, way in the back that moves the derailleur up and down, would this matter?

The bottom bracket width is 68mm.

Ah yes, the B-screw is the vertical screw that changes the angle of the derailleur? What is the best way to fiddle with this screw? I'll check to make sure that the upper pulley is as close as can be to the cassette with the B-screw adjustment.

thanks for the feedback guys
The wipperman connex link must be mounted so that when it is on the top part of the chain the smile is smiling.
 

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Crainius Maximus
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darnelli said:
For the chain, I used a brand new XTR chain with a wipperman power link.

For the derailleur hanger, I also did not use that rear vertical screw that increases tension of the line, way in the back that moves the derailleur up and down, would this matter?

The bottom bracket width is 68mm.

Ah yes, the B-screw is the vertical screw that changes the angle of the derailleur? What is the best way to fiddle with this screw? I'll check to make sure that the upper pulley is as close as can be to the cassette with the B-screw adjustment.

thanks for the feedback guys
Your BB spacers are correct, so we can take that out of the equation. Make sure when you're adjusting the B-screw that you're in the largest chainring and smallest sprocket. Adjust the screw to move the upper pulley as close as possible to the sprocket without letting it touch. Once you've done that, check the clearance in each rear gear while turning the cranks backwards.
 

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Not totally sure if it's the b-screw...how to set b-screw: http://forums.mtbr.com//showpost.php?p=5869368&postcount=5 - disregard the part about using the exposed inner wire to shift into the low gear in the rear, since you have rapid rise and the derailleur will rest there naturally.

Start at the front derailleur and make sure it's properly set.

Use the inner wire to set/check the adjustments on your rear derailleur, not the shifters. Pull on the exposed inner wire to check the shifts.

Have the derailleur hanger alignment checked.
 

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Discussion Starter · #12 ·
TORO1968 said:
Your BB spacers are correct, so we can take that out of the equation. Make sure when you're adjusting the B-screw that you're in the largest chainring and smallest sprocket. Adjust the screw to move the upper pulley as close as possible to the sprocket without letting it touch. Once you've done that, check the clearance in each rear gear while turning the cranks backwards.
so i set it to the smallest in the back and the largest in front...do i do this method even with the rapidrise derailleur?
 

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darnelli said:
so i set it to the smallest in the back and the largest in front...do i do this method even with the rapidrise derailleur?
TORO1968 has it bass ackwards. The fact that it is rapid rise does not affect how you adjust it. Look at Parktool, as I suggested in the second post.

http://www.parktool.com/repair/readhowto.asp?id=64

And.... Be sure to have the bike upright. You can't adjust the b-screw with the bike upside down.
 

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darnelli said:
so i set it to the smallest in the back and the largest in front...do i do this method even with the rapidrise derailleur?
no with rapid rise you start at the big sprocket in the back (middle chain ring)....RD cable is fully slack RD is sitting on the limit screw...

Tighten cable so shift down to next sprocket is good, then check the rest of the cassette.
 

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jeffscott said:
no with rapid rise you start at the big sprocket in the back (middle chain ring)....RD cable is fully slack RD is sitting on the limit screw...

Tighten cable so shift down to next sprocket is good, then check the rest of the cassette.
He was asking about the B-screw.

I get what you're saying about using the different sprockets when installing the cable, but I use the same technique to adjust the cable tension on both types: eyeball the jockey wheel straight with a sprocket in the middle of the cassette. Then fine tune while riding.
 
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