Stripped my (t)rusty inbred down for a trip to the powder coaters but I can not get the drive side crank arm off as the bolt just will not budge.

Middleburn cranks on shimano un54 or 73 can't remember, the bolt is stainless.

I've tried a big lever, shocking with a hammer, repeated blowtorch and gt85, left to soak in gt85. Even with a good allen key the bolt head is now starting to slur.

Any suggestions?

Looks like road bike only for me till i get it fixed

Impact driver?

hmmm good call, I will ask about and see if someone has one.

ofcourse when I get them off I have the difficult what colour dilema!

Wd 4o is a better penetrater, spray it regulerly, then saturate a sponge in WD and place on top of the bolt with gaffa tape for a day or so, top spong up with WD as requierd.
Also have you tried tightening it to crack the seal, if it moves one way it should the other
Hope this helps

Aye, impact driver or tightening the bolt are both worth a try. If they fail then find yourself a small, sharp chisel and use it on the outer edge of the bolt head (or as near as you can get). Support the bike as steadily as you can, maybe lean it against a wall with a block of wood between the opposite crank and wall ... you're trying to direct all the force directly into the bolt rather than allowing it to be 'soaked up' by the bike.

Heat won't have much impact (unless it's serious heat, not a blow lamp) as the bike is acting as a massive heatsink ... shock is what's required.

Oh and either orange or turquoise

right ta, will have another bash, literally, tonight

I couldn't tighten it either

I could be tempted by very bright orange though lime green or purple are the current favourites, with an outside chance of pink*

I don't have a good track record of choosing colours as I had my road bike painted chocolate brown then had the stem painted to match


*my first mtb, a late 80's saracen, was pink...bright manly pink not soft girly pink

my first mtb, a late 80's saracen, was pink...bright manly pink not soft girly pink

Once built a drag bike for a chap, he said he didn't know what colour to have it painted so he'd leave it to me ... he raced a blancmange pink bike for 2 seasons

After the impact driver and chisel, you're next option is drill the top of the head of the bolt. Carefully.

Neither GT85 or WD40 are true penetrating oils, you want to try something like plusgas as well.

Good luck!

Got hold of an impact driver and 8mm hex for tonight's attempt

phew, impact driver worked after some persusion and alternatley shocking it clockwise and anticlockwise. Thanks for the suggestions.

All stripped now ready for painters on Thursday 8-)

Any idea why it seized up in the first place?

I'm wondering if I somehow didn't put a wipe of copper grease on that bolt when I put it in as the other side came out fine. I am usually very careful with things like that...but then I also usually drink beer working on my bike

Too late now but I cut a pair off a mates bike using an angle grinder to cut straight into the crank and axle (cutting the end of the axle in two). We could then just lever the cranks off and remove the BB. This was pretty fatal (for the cranks) but rescued a well loved frame. Was fun making loads of sparks too :D

No offence but my middleburn cranks are probably worth more than the frame!

All ready for a few more years service in purple sparkle

Very nice.

Did you weigh the frame before and after?

Not this one. I did weigh my road bike after it was blasted and then after it was powder coated and the coating added 90g I think. This purple powder coat is really thick so would have been more. I have offset it by adding carbon forks

Really must get my PA painted ... it's starting to look very battle scared, seven years of coaching on it have taken their toll.

Hi Restlessnative, where did you get the frame powder coated? I want to get mine done sometime over the winter.

Pentland Powder Coating in Loanhead (near Ikea), £42 blasted and painted including vat and they were clever enough not to fill the bottom bracket and headtube up with paint

That looks good.
Off topic qeustion: what size tangle frame bag do you have Shawn?

I got a small for a 16", probably could have squezzed a medium in but I wanted it to fit the pompino i no longer have! Want to try it in something?

restlessnative wrote:I got a small for a 16", probably could have squezzed a medium in but I wanted it to fit the pompino i no longer have! Want to try it in something?

Was thinking of getting either a medium or large for my inbred. Do you think they are good? I liked the idea of still having access to a bottle holder.

Yeah it's a good bag but in fairness with a 16" frame the bottle cage is not usable anyway so I might aswell have a full frame bag on. I've been considering not using it just to use a bottle or going the whole frame bag hog.