Grafton Speedstix and BB spindle length

[MuchAlohaNui]

Is there any consideration regarding selection of bottom bracket spindle width for the very early model Grafton Speedstix? When these were produced by Topline (pre falling out / Grafton going their own way) there is something to do with needing to use a wider than usual spindle length due to how the crank arm square hole was manufactured; i.e. using a 113 mm spindle for Shimano cranks, but when switching to the Speedstix needing to go as long as 122 mm or so. Or was this for the Topline cranks only?

In the 1994 Grafton catalog here on Retro, there is no word of requiring a wider bb spindle. Of course, this information at this point is conjecture, so I am seeking clarity from those of you with experience with said cranks. Mahalo!

 

[MuchAlohaNui]

Bumperino.

Not much information I can find over the last few weeks of searching. I did find for Grafton ATB Joystix (circa 1994 - 1995, post Topline split up), triple chainring, a 117.5 mm spindle width is recommended. Other than that, I find information that Topline cranks require a super long spindle of 127.5 mm (circa 1994 - 1995). I don't know a whole lot about my Grafton cranks and whether these were pre- or post- companies fall out such that a mystery to me persists on the year mine were made. For what it's worth they are Grafton Speedstix with 74/110 bcd and were originally anodized 3DV purple.

I use the company Topline synonomously with Grafton until I can deduce what I actually have in hand. Additionally the guy in this thread ended up abandoning his Topline cranks because the bottom bracket requirement was getting absurd. Upwards of 140 mm.

If and I hope IF, these cranks are post Topline 5000 series aluminum cluster F, I have the proper 7000 series aluminum cranks that Grafton originally contracted for and this might clear the air on bb spindle width and lack of potential for crank arm failure. So yeah...spindle width for 68 mm bb shell? Possible year of cranks?

https://www.retrobike.co.uk/threads...cket-trouble-manitou-fs-expert-needed.446928/

 

[MuchAlohaNui]

 

[David Gibson]

There is a chart that I will leave the link to that recommends a 127.5mm BB for the Topline cranks:
http://www.bikepro.com/products/bottom_brackets/bb_comptable.html

 

[fettler]

I think what you have there is a pair of pre fall out Grafton arms. Theses are fully rounded at the back of the pedal threads, Toplines have a machined flat. Spider is held on with an allen screw whereas Topline are riveted. Graftons arms are a bit thicker and chunkier and also therefore a little heavier than Toplines. I have ran them both with a shimano 122.5 although I recall one was on the limit for the front mech to swing out to the big ring at the front. I imagine any variation depends a bit on the individual frame and choice of rings as well.

 

[MuchAlohaNui]

There is a chart that I will leave the link to that recommends a 127.5mm BB for the Topline cranks:
http://www.bikepro.com/products/bottom_brackets/bb_comptable.html

Thanks for the informative link. Much appreciated.

I have ran them both with a shimano 122.5 although I recall one was on the limit for the front mech to swing out to the big ring at the front.

Do you happen to have any old photos of your drive side crank areas on those bikes of yours you are referring to? I'd be real curious to see. I know it's of little help, but the bike uses a 34.9 mm front XTR m900 and 68 mm bottom bracket housing and in some scenarios I know the size of the seat tube requires shimming of the bottom bracket on the drive side to keep the right chain line. I want to avoid extra hardware if at all possible.

 

[fettler]

Here's the pictures of my Topline cranks, I think these are the Xtralight with the extra milling on the spider. Spider still seems relatively flat with the back of the taper. BB is a shimano 122.5, shell is 68mm and front mech was a 28.6mm. I was running 46, 36, 26 or there about. Only clearance problem was actually a tight gap between the big ring and the back of the drive side arm. Made it a bit tricky to squeeze the front mech cage in without clicking on the back of the arm. This wouldn't be affected by the BB length anyway.