That Montjuic of mine

Andy,
I have just messaged a friend of mine who is a cylinder head wizard to see if he's interested in helping you.
If I get a reply I'll let you know by PM.

I once dropped 2 valve heads on my old Kawasaki funny bike na he was able to weld up the head, make new seats, and lap everything in

Neil
 
Thanks Neil, that sounds like a good plan. I think the way forward right now is to bung a used head on the bike, keep the old one and refurbish it at my leisure. I doubt if I’ll sell it because they really are like rocking horse shit and having a good one as a spare will do me no harm at all.
 
It’s good to hear you’re back on track, and likely to be back on the race tracks too. I’m in awe of your perseverance and attention to detail.
 
Needs must and the requirement for extra money on the cylinder head meant funds needed raising so I’ve sold my spare set of wheels. I got £350 for them so if I use man maths and forget the postage from the colonies the cylinder head only cost me £50 :D

The Swedish guy who’s having the wheels is more than happy because, like most Montjuic parts, wheels are hard to come by because they stopped making them close to 40 years ago meaning good used wheels are something to grab and the alternative was a set of cast wheels from an Italian manufacturer at €2,400 :eek:

I just hope this doesn’t come back to haunt me and if I’d been working for the last 3 months I wouldn’t have sold them but it was time to face reality.
 
Andy,
did you get the message about the cylinder head guy?

Shit!

Yes I did and I was going to send you a pm thanking you. I’ll give him a call to discuss the cylinder head because I’ll almost certainly get the ‘spare’ one repaired if only so I can sell it and try and recover a bit more money.
 
Mmmmm.......ummmmm......

You shouldn't have sold those wheels.......
 
Mmmmm.......ummmmm......

You shouldn't have sold those wheels.......

I know. What I should have done was take one of those government bounce back loans they’re peddling and I’d have got a nice cheap rate, nothing to pay for 12 months and totally unsecured by anything belonging to me. I’m a fool to myself :blast
 
Rain stopped play on the Norton which was my planned mission today so I decided to go a bit medieval on the Monty exhaust system.

It’s got an original Sito (loud) race system on it which is in overall very good condition but like everything else painted with heat resistant paint it needs recoating every so often and mine had more than a few rust spots appearing on the headers.

First step was a bit of abuse with the brass wire brush I’ve got for my bench grinder and that removed a few flakey parts plus any rust underneath then I gave it some stick with aluminium oxide paper until there was no visible rust left.

After that I idly considered the best way to prevent the rust coming back in less than 2 years so looked for some 2 pack heat resistant primer came back with a negative unless I order it from the US and pay more in postage than I’d be paying for the can of paint. At this point I remembered that I’ve got some undiluted phosphoric acid so I diluted some by about 20:1 and submerged the headers in a plastic tub. They instantly started to produce bubbles where there was bare metal and traces of rust left behind.
Nice they can stay there until the top coat VHT paint appears.

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I haven’t got a tank I can submerge the collector box and silencers in and more importantly I’d only got a couple of litres of acid left so at this point I went proper medieval and hung the system from the roof then painted undiluted acid on it. It won’t touch the paint but I’d sanded down any areas with surface rust marks so it’ll attack that big time.

If I leave it there the acid shouldn’t all run off because it’s fairly thick and sticks to the surface until it dries and after that it can stay on until the paint arrives when I’ll jet wash it before using solvent to remove anything remaining.

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What’s the worst that can happen
 
Nice one.
I use rattle can zinc spray from Lidl as a base coat before applying black paint to exhausts.....seems to keep the rust at bay for much longer than normal. :thumb
 
You’ve got me thinking about buying a couple of cans of zinc spray to use as a base if it stands up to high temperatures because it’d certainly help flatten the surface a bit where I can’t be bothered to go mad with the mini Scotchbrite pads in a Dremel. I’ve ordered 2 cans of clear lacquer that’s supposed to stand up to 1,000c to go over the 2 pack heat resistant paint because I’ve gone for gloss finish this time so I might as well protect it a bit.

There might be enough black paint left to do my spare set of expansion chambers from the H2 because they’re going on eBay soon. I’m having a cull of all the crap in our garage roof and they’re on the list of items that will probably fetch good money if I can be bothered with the hassle of posting to the US because they’re original ‘70s Denco pipes and the Yanks love that shit :D
 
Why not get lo-iq to ceramic coat them in black?

He did a great job on my brake calipers but the coating is so thin it’d show up every little pit left by rust whereas gopping a copious amount of primer then 2 pack heat resistant paint will hide most of them. I’m hoping the phosphoric acid will do it’s job by converting some of the remaining rust into something that I can smooth out a bit with aluminium oxide paper then paint.

One nice side effect of the acid is that an awful lot of black crud has been lifted from the headers and any corrosion inside will be neutralized. Once I’m happy with the headers I’ll tip the diluted acid into the silencers and collector box in case there’s any corrosion starting in them and it only needs a couple of days to do the job.
 
There's always.......................



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Exhaust wrap. :D :D :hide :hide
 
I know you're joking but....:eek: :eek: :eek: ......

Why on earth do people do that?...

I was. :thumb

I don't know why, either.

It does absolutely nothing at all to improve a bike's performance, only being of scant help in an enclosed car engine bay.

The bikes that have it usually appear to have been snotters, subjected to home butchery, so the owners have probably applied it to conceal Andy's issue of pittted and rusty headers whilst thinking it "looks cool, hipster brother". :D
 
I’ve taken the headers out of the tank and rinsed them off then left them out to dry and all I can say is it fetched the corrosion off but surface rust has reappeared in under 10 minutes.

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I’m not worried because it’ll wipe off with wire wool and the proper eat the exhaust type rust has been dissolved.
 
I’ve taken the headers out of the tank and rinsed them off then left them out to dry and all I can say is it fetched the corrosion off but surface rust has reappeared in under 10 minutes.

961f81d9b75893cc14e695b7452ce978.jpg


I’m not worried because it’ll wipe off with wire wool and the proper eat the exhaust type rust has been dissolved.

This happens when steel or iron parts have been vapour blasted as well.
Flash corrosion due to total degreasing and moisture.
Best thing to do is get them dry as quickly as poss then spray with wd40.:thumb
 
This happens when steel or iron parts have been vapour blasted as well.
Flash corrosion due to total degreasing and moisture.
Best thing to do is get them dry as quickly as poss then spray with wd40.:thumb

That’s what I’ve done. I can wipe them over with solvent before spraying them and the paint should take ok.

I’ll try zinc primer as suggested by Tarka and if it fails I’ll upset him by mixing theirs, there’s, brakes & breaks every day for a year 😀
 
Progress at last.

The forks are complete and will be posted to me tomorrow and the guy doing the wheels has promised they’ll be ready for Monday so I might be able to get it back to a rolling chassis with working brakes by the middle of next week.

I know it’ll stop again once the head arrives and I start to work out what shims I need for the valves but I’ve been assured by a German guy that he has plenty of shims so I need to lap the valves then set about it with a set of feeler gauges and I’m keeping my fingers crossed that the guides are within spec because if I change them I might be struggling with the seats.
 


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