Suntour gurus - advice please

79stef

Retro Guru
I want to run a Suntour MD XC Pro 21 speed set up on my next build. The bike has a 35mm seattube and the crankset is XC pro. I am yet to get the correct bottom bracket.
I have a 73mm Grease Guard bottom bracket with a 130mm spindle and need a 68mm, 115mm spindle (I think) one. So, my questions are:

1.Am I correct in thinking that my setup needs a 115mm spindle length?

2. If I find one, can I do a straight swap of the current spindle from my 73mm Grease Guard bottom bracket to essentially make what I need (68mm BB with 115mm spindle)

3. If the above is possible, are any other spindles compatible for this swap (I believe Campag did the correct sized spindles but unsure if they'd fit -obviously, the GG wouldn't work)

4. Will a modem Shimano UN300, 68mm/115mm bb do the job (I think Tredz do one) in the meantime or is there anything that I'm missing.

Thanks
 
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A 73mm fits in a 68mm frame, have you tried it ?

Yes modern cartridge will do the job.
No other axle will not work (they're the wrong sort of bearings), 73 axle in 68, no idea. they may have different bearing to bearing spacings... or just thicker/thinner cups...

115mm, I think so. Pretty sure I scanned the tech catalogues a long time ago and put them in the archive, could be wrong though.
 
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A 73mm fits in a 68mm frame, have you tried it ?

Yes modern cartridge will do the job.
No other axle will not work (they're the wrong sort of bearings), 73 axle in 68, no idea. they may have different bearing to bearing spacings... or just thicker/thinner cups...

115mm, I think so. Pretty sure I scanned the tech catalogues a long time ago and put them in the archive, could be wrong though.
Yes, the 73mm fits but due to the spacing of the spindle, it won't do up and the spindle length is too long, hence my question about using a shorter one and reusing the cups. Good to know others won't be compatible!

Thanks for the reply - I will have a scour to see if i can find your scanned files in the archive and for now, I'll settle for a sealed cartridge.
 
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?
Though the spindle was 115mm that you have, that doesn't change length with shell size.
Cups should do up, and the lockrings keeps it in place, ok with a bit of thread showing.
I will say I've never tried with a Suntour microlite/GG

A quick look and they (microlite/xc Pro MD, which it the GG version) look to have 68 or 73 stamped on them, so assume they have wider bearing separation. Not the cheapest method..


Wait till what other say though.

Part is BB-SL10-E for other reading (unless using a lower down model)
 
Sorry! My initial post wasn't clear enough. The current spindle length is 130mm.

I will amend the post accordingly.
 
130mm spindle is for the standard 110bcd cranks. I've had both in my time, though must admit I didn't recall it being as long as 130mm.

Cups should be interchangeable but you'd need the correct GG style axle.

You could just use a standard BB, you'd lose the GG but that's all.
 
Thanks. In conclusion - If I don't get hold of one by the time I start assembling the build, I'll get a cartridge bearing to get things set up and rolling and hold out for the correct sized GG bottom bracket (or a lucky spindle find).
 
I have 2 grease guard 68mm bb’s here.
Both seem to have a 126mm spindle.
So I don’t think that helps much. However, would be available if they were any help.
There’s a single set of GG bolts between them, and only one set of bearings, as in a pair.
 
Thanks MatBH5. From what I have read and what FluffyChicken has confirmed, it seems that I do need that shorter 115mm spindle for my set up to work properly - I appreciate the offer though. Hopefully somebody has a 68mm/ 115 lurking.
 
Thanks MatBH5. From what I have read and what FluffyChicken has confirmed, it seems that I do need that shorter 115mm spindle for my set up to work properly - I appreciate the offer though. Hopefully somebody has a 68mm/ 115 lurking.
You need 11?mm for MD cranks (depending on BB shell width) and 12?mm for non-MD cranks, basically. The MD versions are all 'SL', i.e. 'SuperLight', having alloy cups and axles with inserted steel bearing races, and smaller bearing balls as a result.
 

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