Mechanics and Fixing Any Questions Answered

Yeah sorry no picture is unhelpful, unfortunately I'm at home and the bars aren't. The groove is definitely mechanical, bike has barely been used! It literally looks like someone has popped a pipe cutter round the bars and given it a single turn, can feel it with your nail, black paint is broken.

I'd be certain the bars are original so the OD should be a match for the stem, so over or under tightened seems the cause. Thanks for your replies, I'll hang them up in the shed and get some replacements. The drop shape is very... marmite anyway!

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Hi, can someone please help me understand the following problem: the rear wheel is not aligned and I am unable to align it because the frame has vertical dropouts (on a vintage bike). I have tried holding the wheel and then tightening, but it just goes back to it's off positon again.

Would be very grateful for any thoughts or suggestions!

Vertical dropouts like I have on my 70's TT bike hold the wheel in one place only. Have you another wheel you can try ro rule out dishing problems with the wheel.

Is it off to the same place if you flip it and put it in the wrong way round? If yes, probably the frame is fucked, if no then fingers crossed is just the wheel that is dished wrong.

Is the misalignment at the chainstays, seatstays or both.

If it has vertical dropouts I’m not understanding this bit “I have tried holding the wheel and then tightening, but it just goes back to it's off positon again.”. There should only be one position for the wheel in a vertical dropout.

Re thinking, if you flip the rear wheel round won't it be dished completely the wrong way and not fit at all, the freewheel might also catch on the stays?

Is it a nutted wheel?
Could it be shifting as you're getting the nuts tight?

Thank you @midlife @snottyotter and @M_V !

Great replies. I will try putting in the wheel in the other way round, or take off the tyres of a 700c wheel and hope that fits to check.

To M_V

If it has vertical dropouts I’m not understanding this bit “I have
tried holding the wheel and then tightening, but it just goes back to
it's off positon again.”. There should only be one position for the
wheel in a vertical dropout.

Well, it's just my inexperience with vertical dropouts showing - I am just used to horizontal ones. You are right, no way to change that.

I've just received this bike and found a few surprises, incl. incompatible short cage derailleur and front derailleur with triple crank. That wasn't in the deal. The pads on the Mafac centre pulls are all skew (guessing that can be adjusted), so only the corners touch the rims (both brakes and gears need to cables installed). I've never paid this much money for a bike before, so I am at least glad I could get my money back if I wanted.

It was meant as a light tourer, but now finding the chainstays are short (41cm). It's a beautiful bike. I am not that technically proficient, but if I get stuck I can ask my bike shop to check it out tomorrow.

Anyway, will try further with all your suggestions.

Good suggestion, will try checking.

Thanks!

Re thinking, if you flip the rear wheel round won't it be dished completely the wrong way and not fit at all, the freewheel might also catch on the stays?

Almost all wheels should have no dish at all, so if it's all off to the opposite side then it has some dish and is wrong, if it's off to the same same side then it's more likely the frame is off, both could also be true but it's an easy thing to check first. An easier thing to check before that is that you haven't got the QR skewer springs on wrong.

An easier thing to check before that is that you haven't got the QR
skewer springs on wrong.

Thank you!

I must admit, I don't mind getting to grips with this if I had paid far less. But for this kind of price tag, I feel I really should be able to at least hop on and ride. Starting to feel slightly resentful now towards the seller, as I fiddle about in my own way.

Thank you!

Was it this?

Morning all, I've had a nightmare and snapped one of the two crankbolts on some cheapo hollowtech cranks. Longshot but is anyone in Herne hill area able to give me a hand extracting the snapped bolt I've already had a go with a bolt extractor and no luck.

Hah, not there it. Mr Slowness here.

Will let you know how I fared later on. Thanks for your help!

I exchanged the QR skewer for a Pitlock one and then renistalled the QR.

The situation was the same - the rim seem centred at about 12mm each way. The tyre though is also the same: one side has a gap of about 4 or 5 mm (just like my racing bike clearance), the other side about 7 or 8mm. I can stick a small plastic item through one side, but not the other.

I've made sure there sufficient air and when I spin the tyre, it appears to remain more or less constant in its sideways width. Could it be the frame itself?

The seller claimed that the bike was designed for 650b with a max. tyre width of 40mm. That was a big reason why I bought the bike. If one side is the same as my racing bike, then I wonder how that could be enough clearance for such wide tyres.

In the first photo, before he changed out the components, he had 28mm tyres installed. On receiving the bike, it had older 32mm tyres on. So now I am wondering if there was a reason for not having fatter tyres on. I don't have such tyres to test it, but I assume the gap between tyre and frame will get worse.

32mm tyres are fine, but there are huge 10mm gaps between tyres and mudguards and it looks quite ugly.

Thanks, was just trying to mull this in my mind and coming up with 2 answers. Got confused between the rim sitting between the hub flanges and the rim sitting between the dropouts.... Duh!

LH crank arm on a non shimano HT2 crank? Seen plenty of them off amazon/aliexpress recenty, some with 3mm head allen bolts, joke! If its one of those then likely just replace the crank arm or set, new bolt will only break again as they are just engineered/built wrong.

Standard snapped bolt etiquette...
Centre punch bolt from the side of the load, to loosen it in threads, then try and twist out with
good pliers (Geodare/knipex etc)
If its a proper drill out job, unless you have a pillar drill and work holding devices and your time is worth nothing, your better off getting a new crank arm.

So when you flip the wheel the right way/wrong way, the gaps between rim/effective tyre clearance is exactly the same or changing by 12mm?

I've just checked now. The wheel has moved even further towards the same chainstay side, where clearance was less previously. So now the rim clearance is something like 8mm and 16mm, or thereabouts. The tyre on that side has also moved closer to the chainstay - to within about 2mm. Strangely, the wheel now also has a sideways play of about 1mm, even though the skewer has been tightened.

Your spot on, crank bolt was soft as cheese. Tried drilling and using a bolt extractor but it's a lost cause I think.

Sounds like the frame is out and maybe the wheel was adjusted to compensate a little, or is just also out. Get a piece of string and tie it round one dropout, run it round the headtube and back to the other dropout (same side as the other) look at where the string goes past the seat tube, should be a similar distance both sides.

This is amazing help. Thank you!

Found some string and will do.

The distance is the same (35mm).

try it this way

https://www.youtube.com/watch?v=dUPAKqS3dt8