Crankset trouble '86 Bridgestone conversion
#1
Junior Member
Thread Starter
Join Date: Oct 2008
Posts: 10
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Crankset trouble '86 Bridgestone conversion
So I have this '86 Bridgestone Mb-3 that I am currently converting to fixed and I need some help. A friend hooked me up with some parts and I bought a Soma Hellyer crankset off of him as well. I've had a 26'' rear wheel built on a surly hub meant for a frame like mine but the chain line is way off. Even with a new bottom bracket and short spindle the chain line with the Hellyer is ugly. I can't mount the chainring on the inside of the spider guys because there is no beveled edge or zone meant to have something mounted on it. I've looked for another crankset of about the same quality that I can mount the chainring on in a way that will remedy my chainline problem but I'm having a hard time finding something that works. Any suggestions on a crank set that has a low profile, in other words, one that will be closer into the frame and allow for better chainline. I do appreciate it
Willy Beamin
Willy Beamin
#4
Beautiful Member
Join Date: Sep 2004
Location: Pittsburgh PA
Posts: 653
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Likes: 0
Liked 0 Times
in
0 Posts
Any chance that you're mixing MTB and track parts?
MTB BB shells are 73mm, while road bike BB shells are 68mm. Not sure about the Bridgestones, but I'm assuming it's got a MTB sized shell. If you're using a road BB in a MTB shell, that could be your problem right there. If not, you'll need to track down a 73mm square taper BB that has a 110 mm spindle for a 42mm chainline, or if you're using the surly big (130mm) hub, 115 for that hub's 47mm chainline.
Pics would probably help.
MTB BB shells are 73mm, while road bike BB shells are 68mm. Not sure about the Bridgestones, but I'm assuming it's got a MTB sized shell. If you're using a road BB in a MTB shell, that could be your problem right there. If not, you'll need to track down a 73mm square taper BB that has a 110 mm spindle for a 42mm chainline, or if you're using the surly big (130mm) hub, 115 for that hub's 47mm chainline.
Pics would probably help.
#5
Yup
Join Date: Jan 2004
Location: where the sunbeams end and the starlight begins
Posts: 3,083
Bikes: Kona Unit, planet X cx bike, khs fixed gear
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 9 Post(s)
Likes: 0
Liked 6 Times
in
5 Posts
Did you get the mtb surly hub, 135mm size? I have one and am able to run my chainring on the outside of the spider for an excellent chainline. My 130mm hub on my othe bike needs to have the chainring on the inside of the spider, and even with the shortest bb it is still about 3 mm off. Not enough to cause any problems though.
You can try the 67.5mm rule to see how things are lined up. Flipping the cog can help as well, making sure the flat side is facing out.
You can try the 67.5mm rule to see how things are lined up. Flipping the cog can help as well, making sure the flat side is facing out.
__________________
When sadness fills my days
It's time to turn away
And then tomorrow's dreams
Become reality to me
When sadness fills my days
It's time to turn away
And then tomorrow's dreams
Become reality to me