welding motorcycle cylinder heads

[mechanical music]

Start with good old petrol then some water soluble degreaser. Just before welding clean the immediate area with acetone and a wire brush

thats great, i think i might be in luck as ive got a few liters of oldish petrol, acetone and some muck off bike cleaner, thanks for your help

 

[Shox Dr]

To be honest all that needs doing again completely or it will just fail.
For a start the head is absolutely filthy and the weld has porosity down the side of the post so it's compromised.
The gasket seat is also butchered so it needs building up and re boring.
Once you drill and tap the holes I'd be surprised if there isn't voids in the thread.

No way has that had enough heat to weld those lugs. The surrounding dirt would have discoloured from the heat

I smell a rat. I would like to know what was used

 

[mechanical music]

not sure, ime certainly not happy with it, ime going to clean the whole head, and take it back to be redone, ile never use that company again

 

[Fazerruss]

not sure, ime certainly not happy with it, ime going to clean the whole head, and take it back to be redone, ile never use that company again

Be wary in case they make it worse. You need to see if they have the equipment to do the repair properly. Once its welded up it needs putting on a milling machine with a boring head to re shape the exhaust port. This task can't be done by hand with a grinder.
To be honest I'd ask for your money back and take it somewhere else

 

[mechanical music]

i think your probably right, i think theve got all the right gear with no idea, ime just glad all 8 posts didnt need doing, ime not to worried about the milling side of it as ime sure i could maybe use the small dremel rougher ive got from making a guitar to glide across a straight edge to skim the posts tops, and the exhaust gasket surface seems to be minor so hopefully an easy fix with a tiny skim with high temp epoxy, going to ask my brother in law if hes got a tig, thanks

 

[Brad93]

one of the posts was damaged and some was drilled out wonky and messed up, i paid a pro to repair 2 stud posts, apparently he had to grind the whole posts off and built them back up with tig and charged me £40, so thought i would rather try to do any others myself if poss, also wouldnt mind having a go of alloy welding on a scrap head, thanks for your replies

£40!

you've had a bargain there mate, i suggest you promptly return to him to have the others done.

 

[willie.macleod]

No way has that had enough heat to weld those lugs. The surrounding dirt would have discoloured from the heat

I smell a rat. I would like to know what was used

I agree, I think it has been filled in with Lumiweld rods or one of the many copies, can't believe they wouldn't even clean it first.

 

[mechanical music]

£40!

you've had a bargain there mate, i suggest you promptly return to him to have the others done.

i guess you havent seen the damaged caused by the welder and big holes in the weld

 

[Shox Dr]

I agree, I think it has been filled in with Lumiweld rods or one of the many copies, can't believe they wouldn't even clean it first.

Somethingk like that. You would need to cook the bejabers oot of that before a rod went anywhere near it

 

[Brad93]

I often get involved in this sort of work and to be honest i generally leave the finishing to the customer.

I'll put the weld metal on, do the rough grinding, you do the filing. Then if you take too much off or don't get the shape right it's nothing to do with me.

Vapour blasting cylinder heads before welding is a terrible idea. The beads peen the surface of the soft material closing the pores over the dirt trapping it inside.

Hot detergent wash, or hot solvent wash, is the way forwards. Obviously you need to be careful with acidic/caustic cleaners especially at elevated temperatures as the metal can be degraded very quickly.

 

[Brad93]

i guess you havent seen the damaged caused by the welder and big holes in the weld

what i'm getting at is a proper job would have been north of £140, what did you expect?

 

[Shox Dr]

what i'm getting at is a proper job would have been north of £140, what did you expect?

looking at the state of the head I doubt the bike's worth 140quid

 

[mechanical music]

what i'm getting at is a proper job would have been north of £140, what did you expect

what i'm getting at is a proper job would have been north of £140, what did you expect?

i understand the cost, but i was given a quote to repair it, not cause damage that wasnt there to start with, i thought by taking it to a pro welder, the end result would be a proper job or he could have at least told me the proper price to repair it

 

[mechanical music]

looking at the state of the head I doubt the bike's worth 140quid

the head came off ebay not my bike

 

[Fazerruss]

looking at the state of the head I doubt the bike's worth 140quid

You'd be surprised what some of the bikes are worth these days. I'm starting to get repairs in for bikes of that era now as they are becoming more collectable. Even quads are having big money spent on them to return to original condition.

This is a Banshee case I did last week . It needed major reconstruction

 

[mechanical music]

I often get involved in this sort of work and to be honest i generally leave the finishing to the customer.

I'll put the weld metal on, do the rough grinding, you do the filing. Then if you take too much off or don't get the shape right it's nothing to do with me.

Vapour blasting cylinder heads before welding is a terrible idea. The beads peen the surface of the soft material closing the pores over the dirt trapping it inside.

Hot detergent wash, or hot solvent wash, is the way forwards. Obviously you need to be careful with acidic/caustic cleaners especially at elevated temperatures as the metal can be degraded very quickly.

that was exactly what i asked the welder to do, him just weld it so it would cost me less and i could take my time to shape it, but he went and ground it too much anyway, ive learned not to use caustic after causing a cloud of smoke from a bucket years ago when trying to clean a 125 head

 

[Keithmac]

You've got more than £40 worth of welding already, can't understand if you're in the trade what did you expect?.

 

[mechanical music]

You'd be surprised what some of the bikes are worth these days. I'm starting to get repairs in for bikes of that era now as they are becoming more collectable. Even quads are having big money spent on them to return to original condition.

This is a Banshee case I did last week . It needed major reconstruction

View attachment 371973

your repairs are clearly done with a passion, which is how it should be done, unlike my botched job

 

[mechanical music]

You've got more than £40 worth of welding already, can't understand if you're in the trade what did you expect?.

ime not in the trade, i simply took the part to a welder, got a quote, agreed the price and was given back a botched job, if it should have cost more i should have been told the correct price first as i dont know what the costs are, thats his job

 

[Keithmac]

What actual part if the job are you moaning about?, looks like you've got your moneys worth.