RRussellTx - 1974 Commando 850 Project

MichaelB said:
Grer Marsh has good pricing on Tri Spark, he has wiring harness info on his website.
He may build a harness for you also.
Click to expand...
Thanks!
I’ll be reaching out to Greg as my first stop once I get my parts list organized.
 
I picked up the parts from the Powder Coater and I think they did a really good job!
We will see once it goes together, but I'm happy for now.

Also, I talked to Greg and he straightened me out on sequencing and recommended cNw to do the breather mod and clean up some of the parts.
What recommendations do you guys have for what to send to cNw to clean up or modify?
I can polish parts on my buffer wheel but I can't do the blasting finishes.
Again, I'm not looking for a high performance machine but I would like a very clean, reliable and original-ish bike.

Powder Coat 4.jpeg

Powder Coat 4.jpeg

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Powder Coat 2.jpeg

Powder Coat 2.jpeg

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Powder Coat 3.jpeg

Powder Coat 3.jpeg

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Powder Coat 1.jpeg

Powder Coat 1.jpeg

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RussellTx said:
Also, I talked to Greg and he straightened me out on sequencing and recommended cNw to do the breather mod and clean up some of the parts.
What recommendations do you guys have for what to send to cNw to clean up or modify?
Click to expand...
I do my own "make new looking" but you can send all needing it to cNw. For non-72/73 750s I send the crankcases for the cNw breather if the engine is apart and have them do the cleanup. If you can't do them yourself and want new looking, send the empty: crankcases, gearbox shell, gearbox inner cover, and head.

While you're at it, send the oil tank (does not need to be clean). They come back completely clean, leak free, rear mount doubled, bottom mount removed and the bottom doubled to prevent future leaks, and powder coated.
 
If you are looking to have machine work done, such as cylinders bored, new valve guides and seats and crank ground, I would highly recommend Big D cycle in Dallas. They are a real deal Brit shop going back many years. Just visiting their shop is like being in a candy store. They focus mainly on Triumph and Vincent but they are quite capable of doing Norton machine work.

Home - Big D Cycle

SELLING AND SERVICING BRITISH MOTORCYCLES SINCE 1963
bigdcycle.com bigdcycle.com
 
htown16 said:
If you are looking to have machine work done, such as cylinders bored, new valve guides and seats and crank ground, I would highly recommend Big D cycle in Dallas. They are a real deal Brit shop going back many years. Just visiting their shop is like being in a candy store. They focus mainly on Triumph and Vincent but they are quite capable of doing Norton machine work.

Home - Big D Cycle

SELLING AND SERVICING BRITISH MOTORCYCLES SINCE 1963
bigdcycle.com bigdcycle.com
Click to expand...
I thought they farmed out the machine work?
 
marshg246 said:
That's what I heard and when I wrote to them asking about boring or where to get it done, I got crickets.
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Any work they direct to their machinist, makes their jobs take longer.

P.S. a phone call will work much better than an e-mail.
 
Consider have the seal conversion work on the kicker, gear change and tach drive.
CNW can do all this.
The oil tank mod is great highly recommended..
They have propensity to leak at the mount.
CNW mod eliminates it..
 
I wasn't aware that Big D farmed out their machine work. I always just dropped the parts at their shop. I would assume that they hold whoever does their work to a high standard.
 
htown16 said:
I wasn't aware that Big D farmed out their machine work. I always just dropped the parts at their shop. I would assume that they hold whoever does their work to a high standard.
Click to expand...
Last time I talked to Keith was 2010 and seem to recall him telling me he used a nearby machine shop. Who knows, maybe he bought the shop! I haven't been in the biz since 2018 and the last time I talked to him was when i was picking up a "bitsa" 67 TR6 to fix up for my oldest brother.
 
I stopped by Big D Cycles on my way to my parents place. They do still do the machining in house on most items. They do outsource some of the more complex jobs but I did not ask too many questions.

I left them the old cylinders to see if they could be saved. Those will be done in house and he said they could also do the heads if I chose that route.

Really nice place and friendly people.
Thanks for the heads up!

Big D Cycles.jpeg

Big D Cycles.jpeg

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RussellTx said:
I stopped by Big D Cycles on my way to my parents place. They do still do the machining in house on most items. They do outsource some of the more complex jobs but I did not ask too many questions.
Click to expand...
I'm really glad to hear that!
 
I'd take the head in and have them mic the internal guide diameter and valve stems. If they are still in spec you might get by with a light lapping of the seats. But if the guides are worn, they need to be replaced. If the guides are replaced then the seats need to be recut because the seat is no longer concentric with the new guide. If you are putting new guides in you might as well go with new valves and springs. Also, if the valves have been lapped aggressively the seats may need replaced. Getting the head done right is the key to a good running engine. I'd let them do an evaluation of what you have to work with.
 
The bikes only done 8,500 miles.

Unless you ‘want’ to do it in order to fit fancy new parts, the head should certainly not ‘need’ intrusive work like new guides and seats etc.

A good strip, clean, lapping in, etc is really all that should be needed.

I’d check the springs though. If stood for that long it’s likely the springs on the valves that were open are now compressed a bit. If so, new valve springs would be a nice treat for the old girl.

I’d check the head is flat, again, with that mileage I would assume it will not need a skim, but check, don’t assume !
 
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