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Discussion Starter · #1 ·
I am looking to install a set of turbines (just bought) in square taper but am not sure what size bottom bracket to purchase? It is a triple. Should I be getting a 73 x118 or 68 x 118?
 

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Discussion Starter · #2 ·
No help? I see from searches, granted they were several threads from 2009 that the BB shell is 73 not 68. As far as spindle length, I have seen in searches many different lengths but for a triple crank (RF turbine) I would need something around 118. I am looking to run 20/30/42 if possible.
 

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mlk3454 said:
No help? I see from searches, granted they were several threads from 2009 that the BB shell is 73 not 68. As far as spindle length, I have seen in searches many different lengths but for a triple crank (RF turbine) I would need something around 118. I am looking to run 20/30/42 if possible.
Anything over a 40T will need careful attention to spindle length to avoid clearance issues and chainstuck. I have the RIP and the JET and run a set of old Turbines on my JET with a 2 x 9 drivetrain using a 27/40T set of rings and a 121mm White Industries square taper BB. On the RIP, I use Octalink with the old Shimano XT cranks with 20/30/40 rings and got away with 113mm spindle thanks to the 40T. I couldn't get the 44T big ring to work with longer spindles 118 and 123 due to the chainstuck issues. You could start with the 118mm spindle length, but it wouldn't surprise me if 121mm or more would be the final solution for clearance issues. At least the 42T has a better chance of success than my 44T did.

Have you read the RIP and JET clearance issue threads?
 

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I do have a spare set of old Turbines in square taper and a 42T ring in the parts bin I could mount up on my RIP and check for you. I just need 24 - 72 hours to do it as I've got a busy weekend.

It would cost you at least a beer...
 

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Discussion Starter · #5 ·
I have but was hoping that since the turbines have been around awhile that someone might have figured out a good spindle length to avoid chain suck/stuck. I was guessing 118 but wanted to double check here before I picked one up. I could always pick up a couple cheap shimano bbs and see from there. I was hoping to be able to purchase 1 and forget about it too but it seems like running triples on the RIP is anything but plug and play.
 

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mlk3454 said:
I have but was hoping that since the turbines have been around awhile that someone might have figured out a good spindle length to avoid chain suck/stuck. I was guessing 118 but wanted to double check here before I picked one up. I could always pick up a couple cheap shimano bbs and see from there. I was hoping to be able to purchase 1 and forget about it too but it seems like running triples on the RIP is anything but plug and play.
One of the oddities I find with my 2 particular sets of square taper Turbines is that they sit on the Race Face Taperlock JIS spindles a bit different than other BB spindles (like a Shimano for example).

The Phil Wood BB's look to have some very nice options to work for you. I don't understand their BB's totally, but know that they have R+3, R+4, etc... spindles which - at least to my understanding - is that you can buy that version with the right side sticking out 3 or 4mm from the get go. In addition, they are adjustable chainline BB's so you would be able to dial in everything very well. The question is which length spindle to start with. I'll mount up my stuff this weekend on the RIP and do some measuring for you to at least get a starting point.

What's the BCD pattern on your turbines? 94/58 or 110/74mm? There might be a 40T large chainring option available which would remove all concerns of any chainstuck issues on the RIP for a triple.

Can't do it tonight - I'm heading to the opera....

BB
 

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Discussion Starter · #7 ·
I appreciate any and all help Bruce! My turbines are 94/58. I picked up a middleburn 42 for a song (wanted 40 for better fit) but I dont mind the extra 2 teeth if I can get it to work.

Enjoy the opera :p
 

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Discussion Starter · #8 ·
Any luck BB? I would love to get some simple BB like a UN series shimano but I am thinking I will have to end up with a Phil Wood R+5 in something like 119 to get more movement in order to guarantee clearance of my 42t ring...
 

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mlk3454 said:
Any luck BB? I would love to get some simple BB like a UN series shimano but I am thinking I will have to end up with a Phil Wood R+5 in something like 119 to get more movement in order to guarantee clearance of my 42t ring...
I'm doing it this morning. I'm going to do some measurements as well to see exactly how far the big ring has to be out from the center of the seat tube to prevent any chain stuck issues with rings like 42T and 44T. Give me a few hours. I'll snap some pictures while I am at it.

Coffee is a brewing...

BB
 

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Discussion Starter · #10 ·
I am patient. I cant build up for a few weeks while I wait for the rest of parts to come in anyways :p
 

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mlk3454 said:
I am patient. I cant build up for a few weeks while I wait for the rest of parts to come in anyways :p
Okay, first things first. The new JET and RIP frames for a triple pretty much are in the "happy territory" with a chainline of 50/51 - 51.5mm depending on ring size - outer ring that is. This is a bit more out to the right than prior years where mountain bikes were in the "happy territory" in the 47.5 - 50mm Shimano standard range.

And we do know this for the RIP 9 - Truvative Stylo has a 51-51.5mm chain line and produces no chain suck issues with a triple. It's when we get narrower than that 51.5mm - especially with 42 and 44T big rings that the stuck chain issues rear their ugly head.

There is a measurement called W-3 in the SRAM drivetrains which is the measurement from the center of the seat tube to the center of the outer ring. This illustration is for 2 x 9 or 2 x 10 drivetrains, but you get the picture of what W-3 is.



On my RIP 9 running a 40T ring on my triple Shimano XT, that measurement is 56.5mm. I have no chainstuck issues due to the smaller outer ring of 40T providing plenty of clearance between ring and yoke for anything to get stuck. And because of this, I run a shorter spindle 113mm BB and a 47.5mm chainline on my RIP. That gives me a Q-Factor of 171mm and you can see why I didn't really want to go wider with that. I tried 118 and 123 with the larger 44T ring and no go on the RIP as the chain would get stuck.

I went out and first tried a 110mm square taper (Race Face Taperlock Ti) BB. Way too short for a triple with a 42T to avoid chain stuck issues. Scratch. That W-3 measurement dropped way down to 47.5mm.

I then tried a 122mm Shimano square taper bottom bracket. That increased my W-3 measurement to 58mm - a full 1.5mm more than on my RIP's triple with the 40T. Got me right in the range of the 51-51.5mm chainline with what looks like acceptable clearance for a 42T large ring on the RIP. I did not mount up the other arm and take it for a spin to see if I could recreate chain stuck due to it raining. But for me, I would use the 121 or 122mm spindle length as my starting point with a 42T ring based on what I saw and measured this morning in the garage.

I don't have a 118mm spindle to try, so I can't determine if losing 1.5mm on the right side would work or not, but if you have a 118mm square taper with an adustable chainline where you could push it out to the right those 1.5mm - it should be good to go. I would certainly use zip ties around the yoke if going with the 118mm spindle length for extra insurance.

If you want to go weight weenie, White Industries makes an excellent 121mm Ti BB in square taper. Weighs 162g - or the steel one for 226g. They are not adjustable chainline, but the 121mm is working perfectly with a set of Race Face old school Turbines on my JET 9 with a 2 x 9 drivetrain that has a 42T ring as the outer ring which I am running in the middle slot. So I'm pretty confident the 73 x 121 White Industries Square Taper would be a good combo on the RIP for clearance. That's not to say it is a guarantee, but it sure looks like it to me. I just am more hesitant to recommend a 118mm length in case it was too narrow to prevent the 42T from getting a stuck chain. But if you've got one - give it a try before ordering the next length of 121 or 122mm. Going inexpensive with the tried and true Shimano square tapers - you can save a lot of money and they last forever (I've still got some working well from 1989). They just weigh a ton.

Hopefully that helps. I didn't take any photographs because my daughter doesn't know where she left my camera. Yikes!!!!

BB

Edit: P.S. Q-Factor with the Turbines and the 121mm spindle is 172mm which is certainly acceptable.
 

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Discussion Starter · #14 ·
Well it looks like I will spend the next couple weeks trying to pick up a PW in 119 R+5 or so and should be all set. Hopefully I can score a deal on fleabay as I am not overly excited to drop $140+/- on a BB. BUT it gives me the most options out of 1 purchase...I appreciate the measurements. When I get it all together in a few weeks I will update the thread with some measurements. I may still put a couple zip ties on there to be safe too :p
 

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If it helps, I'm running DaVinci cranks with a 2x9 20/34. The BB is an older XTR 73x107, could run a Philwood 105 someday. Those cranks allow a narrow BB, and I have no clearance or chain suck issues. I havn't tried a triple with that combo yet.
 

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mach.84 said:
If it helps, I'm running DaVinci cranks with a 2x9 20/34. The BB is an older XTR 73x107, could run a Philwood 105 someday. Those cranks allow a narrow BB, and I have no clearance or chain suck issues. I havn't tried a triple with that combo yet.
If you read or check the entire thread on clearance issues for the RIP, you'll find that your double ring cranks with a 20 and 34T ring are not the issue within this thread. It is entirely related to the large or outer ring of a triple crank on the RIP and the possibility of chain stuck happening when running the chain in the middle or small ring as the chain bounces up while the rear suspension is active due to the clearance between the chainstay/yoke area and the large ring. This could cause the chain to get stuck between the chainstay/yoke and the ring as pictured in that thread linked above. So the bottom bracket spindle length for the triple ring is quite crucial compared to the needs of your configuration of a 20/34 ring combo. A spindle length of 107mm or 105mm on his Race Face Turbine cranks with triple rings with the outer ring being 42T would render the outer ring useless - although the granny and middle rings would be okay.

BB
 

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Discussion Starter · #17 ·
Another thought since you have experience and have measured a bit...is there a magic number for clearance between the big ring and the chainstay that I should shoot for when I get the adjustable BB?
 

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mlk3454 said:
Another thought since you have experience and have measured a bit...is there a magic number for clearance between the big ring and the chainstay that I should shoot for when I get the adjustable BB?
I wish I knew. I just know that there is plenty of a clearance with a 40T for a chain not to get stuck between it and the yoke/chainstay area. What is the measurement difference between a 40 and a 42T in terms of millimeters?

Here's the perfect clearance visually thanks to the 40T ring I run..



You'll know right away if the clearance is not enough as the chain - while on the middle ring - will jump up and get stuck between the big ring and yoke/chainstay. You could go cheap and purchase a Shimano 118mm and 122mm x 73mm BB for $15 - 20 each. Then, when you know which spindle length works the best with no chain stuck issues, sell the other one on eBay. And if you don't want to stick with the boat anchor Shimano - go weight weenie if you feel like it and get a Phil Wood Ti or White Industry Ti.

I really wish I knew the intricacies of the Phil Woods BB's and how that right side additional millimeter system (R+_) worked. Did you call them to see?

BB
 

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Discussion Starter · #19 ·
I am trying to win a used PW on ebay at the moment. According to their pdf below it seems like you install the bb, screw in the non-drive side and set the appropriate distance on the drive side with 5mm or less of threads showing. It doesn't seem like the best closed system but it is the best as far as 1 bb for the job...

http://www.philwood.com/philpdfs/crankbearinginstallationguide.pdf
 

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Discussion Starter · #20 ·
Just an update. I got a great deal on a PW 119 +5 bb and a set of english mounting rings. I just have to wait until I can get the bottom bracket tool in so I can install and give the thread an update on measurements and if I am getting chain suck/stuck.
 
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