Aargh! Chainring touching the chainstay!

[GT-Steve]

I had an action tec (I think) Ti BB tha was 127mm, so they are available.

 

[legrandefromage]

tricky...

my nos 127/73 UN72 came all the way from Canada

Try FMJ

 

[legrandefromage]

I had an action tec (I think) Ti BB tha was 127mm, so they are available.

http://www.actiontec.us/attack.htm

 

[We_are_Stevo]

I hate to state the bl**din' obvious but it's quite clear from your photo's that the frame was designed for a compact chainset...

...if you fit a long enough spindle for the big ring to clear the stay the granny ring is going to be a mile out and your chain line from the big ring will be in the next street!

Fit a compact chainset and your problems will immediately disappear.

I speak from bitter experience as I fitted an Ultegra triple with a 52T big ring to my '97 Kilauea (I was living in Cambridge at the time and enjoyed being able to keep up with the Uni Roadies), and even with the longest Octalink I could find I still had the same problem. I ended up dressing the stay back with the rubber-handled end of my claw-hammer and it was fine after that! :shock:

 

[legrandefromage]

I hate to state the bl**din' obvious but it's quite clear from your photo's that the frame was designed for a compact chainset...

...if you fit a long enough spindle for the big ring to clear the stay the granny ring is going to be a mile out and your chain line from the big ring will be in the next street!

Fit a compact chainset and your problems will immediately disappear.

I speak from bitter experience as I fitted an Ultegra triple with a 52T big ring to my '97 Kilauea (I was living in Cambridge at the time and enjoyed being able to keep up with the Uni Roadies), and even with the longest Octalink I could find I still had the same problem. I ended up dressing the stay back with the rubber-handled end of my claw-hammer and it was fine after that! :shock:

The frame in question is from 1993, compact had yet to make a full entrance.

and running 52t on a skinny steel frame such as your Kona is easy - try it on a fat framed bike for the real test:

 

[We_are_Stevo]

Did the Trek not come with XT M737 compact then, or was that the '94 model??

 

[legrandefromage]

Did the Trek not come with XT M737 compact then, or was that the '94 model??

M730 for the 93.

 

[My_Teenage_Self]

Fair point, but the distance to centre of the seat tube to middle ring is currently 45mm, wheras the ideal should be around 47.5-50mm (according to sheldon brown)

The granny ring is currently hovering just over the edge of the BB shell, so I'm not too worried.


Question:

Assuming a decent Ti bb weighs 170-190g, how much extra would an equivilent steel axled BB weigh? Alloy cups and sealed bearings.

I may have found a NOS 127/73, but it's steel axle.

 

[FluffyChicken]

how far is the none drive side out and what bottom bracket is it.
You could drop to a 44 or 46 outer if you are up at 48 say.

I do not know what RS2's should be using (there is a thread in FAQ Bike oddly enough). Taking Middleburns site that only refers to the new ones.
I will say the 50mm chainline was there for fat tubes, 73mm shells and often would be using the widest band size front mech.

anyways, if you get really stuck send these chaps a message (none used by me, they're a different league)
Royce who'll make about any weird size you can think of.
http://www.royceuk.co.uk/Bottom-Bracket ... -cups.html
or Phil
http://philwood.com/store/page32.html
or...

 

[LeeDevelopment]

TA Specialites BB's too