Mechanics and Fixing Any Questions Answered

Cheers Guv’.

Given that there's still plenty of thread spare, I can't think of any reason not to file down that lip on the outside to make a flat face on the hanger. First though I'd remount the derailleur and manually push it all the way across to check that it can reach the biggest sprocket (or nearly). Otherwise it will never function properly.

Incidentally, does that derailleur not have a B-screw?

Thanks. It does have a b screw but it’s hidden away such that I forget where it is each time! I think the derailleur will just about reach the reach the biggest sprocket but it would certainly make life easier if this frame didn’t have these peculiarities. For what it’s worth, I tried another mech which moves a lot further when the high limit screw is tightened, but I suppose that’s because it’s a 7 speed as opposed to the 10 speed Campag one I want to fit?

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Find a longer limit screw? , maybe pack out the stop that the limit screw touches.

I’d definitely file the nubbin off the outside, probably leave it on the inside to increase the thread engagement.

Is this really true, in all cases of HG ali cheese-hubs? The person is adamant that failure to torque causes all notching issues.

https://thecycleclinic.co.uk/blogs/news/aluminium-freehubs-and-notching#:~:text=First%20notching%20can%20only%20occur,Grease%20freehub%20splines%20lubricates%20them.

Nah, that's BS.

There's always a bit of movement between the splines on the cassette and hub body hence no matter how hard you try to tighten down, it will bite.

It's the soft alloy freehub which is the issue.

Formula/Vision have some aluminium freehub with a steel insert on one of the splines to prevent this. Stop it biting on one point and it stops it all.

The person is adamant that failure to torque causes all notching issues.

It's probably the pre-eminent cause of premature notching, but correct preload is not guaranteed to prevent all notching. As the eagle says, steel inserts solve it, and other manufacturers have them too (Novatec Anti Bite Guard, Bitex Gouge Guard)

Any chance these aren’t M5? Struggling to get a bolt in. Time to run a tap through it?

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M5 and tap yes, remove the wheel though and from the other side.

Thanks. Tap worked a treat and also had the advantage of being immensely satisfying!

Bb386 evo its bloody squeaking when pedalling . Its only 3 months old?

Are you sure it's the BB? Always check first for crunchy bearings

Had it apart this afternoon and its smooth.

You can reinstall it with loctite, etc. But sometimes it's the saddle clamp, the wheel the crank and many other fun times

Generally speaking, if you switch a JIS crankset for another JIS crankset, will your chainline be unaffected? Or do different cranksets sit differently on the taper itself? Thinking of replacing my Lasco CF12 for a FK55 CNC, but not sure whether this will affect my chainline and it's an £80 experiment. If it did affect chainline, what would be there remedy? A different width BB?

Are they both track cranksets? If so then they’re probably both designed for the same bb length.

Yeah, they are both for fixed gear. Just trying to work out my frame BB standard and shell width as a starting point (without disassembling). I think it's BSA 68mm if that's the most common nowadays, it's a Quella singlespeed frame (but not one of their current ones). Might give them a ring. The Lasco CF12 according to this review is "Compatible with 103mm JIS type bottom bracket, 170mm compatible with 3/32in chains, 165mm compatible with 1/8in chains", and on the FK55 SantaFixie page they claim "111 JIS square taper bottom bracket recommended" but I am not sure in what way they "recommend" it.

Does this mean my current BB likely has spindles that are too short? How does one calculate all this stuff to make sure I have the correct chainline? My rear wheel is an older Miche Xpress but surely track wheels all have the same width?

How does one calculate all this stuff to make sure I have the correct chainline? My rear wheel is an older Miche Xpress but surely track wheels all have the same width?

One doesn't calculate, one measures. First you need to know what your existing chain line is, and what BB spindle length you have. Then find out what chain line the new one is supposed to have with the recommended 111mm spindle. Then assume spindles 111mm and shorter are symmetrical and calculate the expected chain line using the new crank and whatever spindle you decide is likely to give the chain line you already have. Then assemble it all and measure the actual chain line and discover that somebody was lying to you. Finally throw it all in bin and buy an Alfine which has a completely reliable 42.7mm chain line and is superior to any square taper crank.

Track hubs are not all the same, and the chain line depends on which sprocket you use, but they are mostly 42-43mm except the ones which are 40mm or 46mm 🙂

Bb386 evo its bloody squeaking

Assuming it is actually the BB, the bit which has some free play on a properly assembled 386EVO system is the axle in the bearing inner races. Make sure the axial preload is set correctly, and keep the axle and inner races clean. Loctite should not be necessary, but a spot of 638 might quieten things down at the expense of making future disassembly harder

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Q: are early sram red (10spd) brake calipers known for sitting low on the wheel or is it my fork? I have 0 clearance between the front caliper and a 25mm tyre sitting on a wide rim and minimal clearance with more traditional 25mm tyre/open pro combo. Fork is from BTwin top of the line 2015 bike. Without answering my own question too much, clearances seem ok at the rear.

Bloody BB refuses to leave me alone; pinging sound has returned after a complete stripdown and running a toothbrush over the frame threads with degreaser. Now my biggest worry is that I may already have cross threaded or stripped part of the BB shell (when I removed the BB there was definitely some thread that had been stripped), since the BB threads themselves seem fine (though I have no idea if it's the cranks being loose on the BB) - is it worth buying a tool to clean/tap my frame BB threads (toothbrush wasn't good enough) or should I just pay the 30 quid for my LBS to do it?

As ever, and totally guessing here, but if it’s threaded it’s probably not your bb.

Tighten up your quick release/wheel bolts, check stem bolts, grease seat post, swap pedals out.

This is a long running saga where I have isolated the problem to the crank area - definitely not wheels since it happens when I alternate from back to front (and vice versa) pressure on the pedals; probably not stem for that reason too, particularly as no pings when out of saddle and pulling on bars in all directions, happens if standing so not seatpost, have swapped out pedals.

The problem also gets worse over time, i.e. if I pull everything apart and put it back together again, I get blissful silence for about 2 weeks, then one ping every so often for another 2, then slowly over another month or so it gets to the point where pedalling out of the saddle has the bike in much protest.

Problem did only arise after I swapped out cranks but I replaced BB apart not long before, so if someone can help me with diagnosing loose cranks that would be helpful.. Have already done up the crank bolts as far as they can go with a 6in 8mm allen key though.

My uneducated diagnosis of the situation is that the suspected cross threading etc may have worn down the frame threads enough to knock the BB ever so slightly out of alignment (I can feel the clicks through the left side crank/pedal) each time it gets pulled in a different direction, although the threading is definitely firm enough to hold everything very, very in place and removing the BB takes a fair amount of effort.

Ah apologies, ignore me then. Good luck