Squeak and bolt problem

[pioneer]

Hi all, I've got an annoying squeak on my Bob Jackson. Thought at first it was the old leather on the B17',but no. Then thought as it had new transmission a few months back,the cranks may need tightening so did that. No. Now working on the chainring bolts, I bet you can guess what I'm going to say next! Four of them tightened up fine, the last little brighter I just can't get right. It's the old problem. The silly little chainring bolt spanner the fits into the reverse of the bolt I can' t grip firm enough. Tried all sorts, even using an old hand vice and clamping it the chainring. I've always thought the whole design of the chainring bolts was terrible anyway, even more convinced now! The slots in the female part are just too damned small for any grip to be found.Grrrrrrr.........
So, any clues please as to how to grip the reverse/female part while turning the Allen key part?
Of course, ones it's done there may still be a squeak. But if it's the BB that's an easy job to do by comparison.

[gaz]

Before I had the right tool I used a flat length of steel bracket that was the right width to slot in, a bit like a sideways screwdriver.

Alternatively get some of the "type b" bolts from Highpath, you'll never need a chainring bolt spanner again.

[pioneer]

Thanks Gaz. I"ll try again tomorrow in the daylight and when so tired. I can't complain, done three rides this week (squeak getting slowly worse) and the bike took a hammering on the Dynamo last weekend. A lot of water on the roads in places which got thrown up from the front wheel over chainring and BB.

[reohn2]

FWIW I always treat the threads on c/ring bolts with copper grease,they tighten up far easier.Also the slightly rounded end of a steel rule makes a good c/set bolt screwdriver and as it's flat it's easier to grip too.

[AndyA]

Truvativ make chainring bolts that take a 5mm allen on one side, 6mm allen the other. Very nice
http://www.edinburghbicycle.com/product ... g-bolt-kit
Or VAR make a wonderful tool for the horrible normal ones
http://www.ebay.co.uk/itm/like/15131502 ... 0&ff14=108

[Brucey]

there is a very simple trick with chainring bolts, all you need to do is this:

1) remove the bolt

2) clean both halves.

3) This is the important bit; screw the two halves of the bolt together so that they go together a little further than normal. All the way if possible. Make sure that you can do this easily with no binding.

4) Lube up the threads (both parts) with copper-ease; run them together again.

5) Install as normal; you shouldn't need a tool to hold the female part of the bolt.

The reason this works is that the thread is cleverly specified to allow tightening without two tools provided that the thread is clean and in good condition. The slightest binding in the threads will inhibit the thing from tightening properly. Having the right tool is handy for loosening partially seized bolts but is a red herring for normal tightening; a used bolt often has enough crud in the screw threads that it won't tighten properly without using excessive torque for which the tool is not designed.

For dealing with seized bolts it is a poor design; an ounce of prevention here is much better than several lbs of 'cure' IMHO.

A few times I have encountered bolts where the two halves will not go together far enough to clamp the assembly; badly made bolts or larger than normal countersinks in the chainrings will cause this.

The thread is an unusual one; I happen to have a tap that is the correct thread and if an old chainring bolt is especially bad I will run it through the female part of the sleeve, but normally this isn't necessary.

BTW once a chainring starts to squeak, it is usually a good idea to remove it and to clean the interfaces; the black crud that develops will often allow further creaking even with well-tightened bolts.

If you are one of these all-weather types, you might wish to consider using stainless steel chainring bolts; I've had a few standard steel ones succumb to corrosion assisted cracking, and stainless ones should resist this somewhat better.

hth

cheers

[pioneer]

Gaz, so how does the B type bolts work? The pic is a bit unclear. Spent more time on it this afternoon. Still can't get any grip on the rear slots. Even filed the spanner slightly for a better fit. Next course of action methinks is to very gently drill it out, as long as I don' t damage the chainring. Will also use copper grease upon the refit, thanks Brucey.

[Brucey]

if you are struggling to undo these bolts here are a few tips;

1) use heat; if you have one of those micro-blowtorches, use that.

2) make a better tool; you need some really hard steel ~1.5mm thickness. I found some blades from a reciprocating saw which were the right thickness and carefully ground a tool to fit. IIRC last time round I put the tool in the bench vice and sat the chainset on top of it; being able to bear down onto the job helps to stop the tool from popping out.

Between both the above I have not had to drill one of these bolts out, not for years, not even on bolts that are totally seized and corroded.

hth

cheers

[gaz]

Gaz, so how does the B type bolts work? The pic is a bit unclear.

The female part has a serrated edge under the lip that bites into the chainring, preventing it from rotating as you tighten.

I had some a while back on a TA Zephyr.

Putting the female part outside gives a clean finish, or would have if I had cleaned it .

[Valbrona]

The slots cut into a chainring 'nut' can be to four or five standards. The Cyclus tool has bits for each type, unlike the VAR one.

[pioneer]

Thanks both. More shed time this afternoon coming up. I've tried the bench vice trick before with an old screwdriver filed to fit clamped in the vice so that is a possibility again. Once all off, I'll put in a new BlackBerry anyway. At least the thunderstorm has stopped and it's a lovely fettling day.

[pioneer]

Ha! My phone auto corrected the double b I wrote and changed it to BlackBerry. Which it is itself. Nepotism I believe!

[pioneer]

Well.... after replacing the BB and chainring bolts, the squeak was still there. So, saddle off and checked all that out. The saddle rails bolt was a little loose, maybe that was it? Another test ride. No. Pedals perhaps? Shimano M520's. Did some research and discovered you need the "special tool" to get them apart and re-grease. Took them off, they seemed fine, still spinning nice and smooth. But put on some spare M540's anyway and went for another ride. Squeak gone, peace at last! Now sent off for that tool, though as the old M540's look better and work fine, may leave them on.
But on the bright side, the bike has had some new bits and I've learnt a lesson about copper grease so it's not all bad.

[Brucey]

unless you have refitted the same pedals with fresh copper grease then it isn't proven that the squeak wasn't where the pedals screw into the cranks. They also squeak where the cleats touch sometimes too. However a squeak from deep within PD-M520 pedals is mighty unusual. The special tool is cheap to buy BTW.

cheers

[pioneer]

Tool ordered from Tweeks. M540's put on with a good dollop of grease and all OK. Yes it could have been the pedal axle and crank interface. The M540's have a larger surface area at the point which sits over the face of the crank rather than digging into it.