Slowest RestoMod Ever

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Sep 1, 2014
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I'm going to claim the record for this...I'm sure!

Background
  • Mid-'80s....Nigeria...Norton Commando discovered by oil worker late father. Exchanged for a tin of grease. Appears to be Nigerian ex-police/army(?)*;
  • Enquiries with Norton Owners Club identifies the bike as a '74 850 Interstate Mk2A. Brought back to UK for bike-mad teenage son;
  • '90-ish.Stripped down, cleaned-up, exclamations of "Bloody hell! That needs a LOT of work!"and boxed-up by young, newly married, (therefore skint) RAF mechanic (me);
  • During the intervening years, the bike is stored. Half-arsed, sporadic work is carried-out, e.g. wheels rebuilt, forks rebuilt, etc., but big stuff avoided;
  • Late-noughties beer-fuelled discussion between father and son..."We need to get that Norton sorted-out!. Bike goes into classic bike shop for restoration;
  • Money spent (£several thousands). Late-father not happy with progress, bike taken back home. Sits in shed;
  • 2014 father dies, son inherits bike. Bike transported to son's shed..."I'm definitely going to rebuild it";
  • Son joins Norton Owner's Club, starts research, becomes inspired by "new" custom/cafe scene, dreams of Fullauto heads, modern brake conversions, etc.;
  • Present day...late 2017...finally started(!). Ex-Norton riding '60's ton-up boy mate, helps to remove engine. Invaluable knowledge remembered after 40+ years since his last Norton strip-down.
First Big Challenge (well, if we don't count finally managing to remove the central, recessed (Whitworth!?!) nut in the head!)

Advice/opinion needed please. Take a look at the photos. Do you think the knackered fins** on the head and barrel are repairable? Daughters' weddings unfortunately discount the purchase of Fullauto or similar desirableness at the moment, so if they're not, then it's not going to be featured on BikeExif any time soon!
https://postimg.org/gallery/1e39qjcna/

* Bike was badly painted all over (and I mean ALL OVER) a horrible mid-blue. later investigation discovered a bottle green colour underneath on the tank.
** Theory is that bike blew the head gasket in the Nigerian bush and was subjected to cack-handed "repairs" by somebody who didn't realise that there's 10 fasteners between head and barrel.
 
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That head and barrel are clearly scrap, order a new head from Fullauto and alloy barrel from Maney. Job done!

Ok, on a more serious level... a 74 mk11a should have the RH10 head (look on top of the head, you should see it stamped somewhere).

These are the good heads! So it’s worth asking the question as to whether or not it’s worth saving. And that looks like a tough call to me!

But, although the damage looks bad, you could easily cut out and file to shape some replacement fins out of alloy yourself, so if you know a competent alloy welder who won’t charge the Earth, it may not be the lost cause it initially appears.

One could argue the same for the barrel, but these do often come up on eBay quite cheaply, so my guess it’s gonna be cheaper to buy a bore-able second hand replacement.

But, whichever way you look a tad it, this project WILL be a money pit... so you’d better start taking a close interest in, and black marker pen to, your daughters wedding plans...!

BTW that must have been a very big, or very posh tub of grease...!
 
That head and barrel are clearly scrap, order a new head from Fullauto and alloy barrel from Maney. Job done!

Ok, on a more serious level... a 74 mk11a should have the RH10 head (look on top of the head, you should see it stamped somewhere).

These are the good heads! So it’s worth asking the question as to whether or not it’s worth saving. And that looks like a tough call to me!

But, although the damage looks bad, you could easily cut out and file to shape some replacement fins out of alloy yourself, so if you know a competent alloy welder who won’t charge the Earth, it may not be the lost cause it initially appears.

One could argue the same for the barrel, but these do often come up on eBay quite cheaply, so my guess it’s gonna be cheaper to buy a bore-able second hand replacement.

But, whichever way you look a tad it, this project WILL be a money pit... so you’d better start taking a close interest in, and black marker pen to, your daughters wedding plans...!

BTW that must have been a very big, or very posh tub of grease...!

FE, thanks for the very useful response. Yes, Fullauto and Maney would be my first choice...however, circumstances, three daughters, weddings, etc., etc.!

I'll check the head tonight for the the RH10 markings. The photos are being considered by a welder at the moment, so fingers-crossed.

On a positive note, the bottom end and gearbox are "in good condition", according to the classic bike shop that did the initial investigation :rolleyes:

Can't comment on the grease, seems like a great bargain, but maybe they knew the true dangers of rebuilding knackered old Brit bikes, sorry, I mean"classic restorations"!!!

Don't be expecting any rapid progress on this saga...(youngest daughter's plans TBA! At least she's in her final year at uni, so that's one less expense!). Let's just say, it's going to be episodic!

Incidentally, the old man was called "Eddie" too, but he was never fast...at least not on a bike ;)
 
FE, thanks for the very useful response. Yes, Fullauto and Maney would be my first choice...however, circumstances, three daughters, weddings, etc., etc.!

I'll check the head tonight for the the RH10 markings. The photos are being considered by a welder at the moment, so fingers-crossed.

On a positive note, the bottom end and gearbox are "in good condition", according to the classic bike shop that did the initial investigation :rolleyes:

Can't comment on the grease, seems like a great bargain, but maybe they knew the true dangers of rebuilding knackered old Brit bikes, sorry, I mean"classic restorations"!!!

Don't be expecting any rapid progress on this saga...(youngest daughter's plans TBA! At least she's in her final year at uni, so that's one less expense!). Let's just say, it's going to be episodic!

Incidentally, the old man was called "Eddie" too, but he was never fast...at least not on a bike ;)

Neither am I... it just sounds good!

Looking forward to the progress reports... at whatever pace
 
RH 10 means you are going to try and save it by sending one of your daughters to trade school to learn
aluminum welding . Try to save it. Someone will have to cut and make up the missing fins. I doubt if it will ever look original after the weldings and grindings are done. You could spray it in heat paint say black so nobody notices much. Or just make more money somehow.
 
RH 10 means you are going to try and save it by sending one of your daughters to trade school to learn
aluminum welding . Try to save it. Someone will have to cut and make up the missing fins. I doubt if it will ever look original after the weldings and grindings are done. You could spray it in heat paint say black so nobody notices much. Or just make more money somehow.
Ha! Now there's a thought! Unfortunately, none of them have followed a mechanical vocation.
 
Bad-ish news! The welding engineer reckons that neither the head or the barrel are repairable :(

Good news! Andover Norton have just emailed me to tell me that they've just taken delivery of a batch of shiny new Fullauto heads!:D

Now, where am I going to find £3k??? Last week's £25 lottery win is just not going to cut it. :rolleyes:

Anyway, as an aside...I took the gearbox out on Saturday...and then I just couldn't stop myself... https://postimg.org/gallery/kqzp8dqe/

So, plenty of cleaning, inspecting, etc. while I save up my pennies. Maybe I'll strip and rebuild the forks next o_O
 
RH10. What's wrong with the previous cylinder head versions? Porous? prone to cracking? Heat distortion? As a clueless Commando owner, I'd like to understand the issues with the earlier heads o_O. I've been scouring Fleabay, but no RH10s to be seen.
 
RH10. What's wrong with the previous cylinder head versions? Porous? prone to cracking? Heat distortion? As a clueless Commando owner, I'd like to understand the issues with the earlier heads o_O. I've been scouring Fleabay, but no RH10s to be seen.

Really only two heads used on production 850 engines, the RH4 and RH10. Other 850 heads listed for high performance and racing use (RH6, RH7, RH8, and RH9), but not commonly available. The problem with RH10 heads is that they are very prone to crack along the valve guide boss. Usually attributed to the factory fitting the guides with too much interference fit. What you would like to find is a nice used RH4 head.

Ken
 
Really only two heads used on production 850 engines, the RH4 and RH10. Other 850 heads listed for high performance and racing use (RH6, RH7, RH8, and RH9), but not commonly available. The problem with RH10 heads is that they are very prone to crack along the valve guide boss. Usually attributed to the factory fitting the guides with too much interference fit. What you would like to find is a nice used RH4 head.

Ken
Ken i think you got it backwards the RH4 heads were as i understand the ones used on the 73 and 75+ 850 which were prone to cracking were as the RH10 were the smaller dia port (30mm i think) on the 74 only were are highly desireable...

but i could be wrong
 
Yes, t’other way around. The RH4 is prone to cracking. It also has bigger inlet ports at 32mm.

The RH10 isn’t prone to cracking and has 30mm inlet ports which are better for performance on the Commando engine.

Tis the RH10 you want.

But so does everyone else...
 
Sure enough, you guys are right. I should have got that straight, especially since I recently had to replace one of the cracked RH4 heads when I built a MK3 for my grandson. I plead old age and diminished capacity.

Ken
 
if you have an RH10, your golden... as long as the intakes haven't been hoged out by some uneducated twit. the fins can be welded then its just a matter of what it will cost to repair vs the cost of a new fullauto unit...
 
Well, I agree with that. If it’s only fin damage, it is repairable. I’d carefully check the head, if the rest is good, I’d look again at fin repairs.
 
His head is pretty knackered.

Slowest RestoMod Ever


Slowest RestoMod Ever


Slowest RestoMod Ever
 
a good cleaning, (hydroblasting etc) and it will change the whole complection. new kibblewhite valves and guides, springs etal, then the studs upgrade and thread repair ... i see a trip for this piece to J. Comstock...

that what i'd do...
 
I appreciate the second opinion on the head - that's very encouraging. Cheers.

J. Comstock's work looks beautiful...shame he's in Colorado...I'm in Northumberland :rolleyes:. Is there a UK equivalent?
 
I count 7 broken fins.

The time consuming part will be dressing the broken fins back so they have a nice weldable join and so they are all accessible to the welder. And then cutting and shaping new fins.

All of that can be done by your good self for the cost of a bit of alloy plate. And sacrificing watching Strictly !

All you’re going to pay a welder to do is approx 14 inches or so of welding. That won’t cost a lot.

If replacement heads were ten a penny, of course it would be a different conversation. But they’re not. A good second hand RH10 could easily cost £500, so I’d say that head is salvageable.

If you do wish to consider having your head worked on by Sir Comstock, Don’t Let the Atlantic put you off. I posted my head to him and he posted it back, I’m in Oxford UK.

Or, keep looking on eBay. USA eBay is probably a better bet that anywhere else. And if you bought one in the US you could get it sent directly to Jim.
 
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