Restoring a MKIII. What mods would YOU suggest?

Lizard King · Nov 25, 2006

So far I've put on a Magura brake cylinder, single Mikuni, and braided oil lines. I've found that a Sportster gel battery fits rather well. I'm replacing the Boyer with a Rita due to the Boyer's problem with electric starters. I've put on new pipes w/ pea shooters.

That's about where the limits of my mechanical ability kick in.

What else should one do to drag the Commando toward the 20th century? Cam? Big Bore? I've actually seen 2 Dureons on ebay in the last month. Balancing? Blueprinting? Compression? Port grinding? Belt Drives? Transmission?

I'm under no illusion that a 30 year old bike will be able to go head to head with anything coming out of Japan. I just want to get the most out of my machine.

Thanks all.

norbsa48503 · Nov 25, 2006

Go threw the cam and the oil pump.
No Need to pull it down just indicate what you have. When you check the numbers against the work shop manual remember the the rocker ratio is 1.13 to 1 or so. When they go it's almost always one lobe going before the other three.
Pulling down the oil pump can show you a lot about what the rest of the engine has been in. Just a good clean up sine up ,lapping in the gears and body is all that's needed. If sumping takes all winter, Just doing this is fine. If it's a quick sumper you may need to look into a pressure side check valve as installed by AMR in AZ.

Coco · Nov 27, 2006

Good question and I'm interested too. With mine I'm doing a better front disc system, putting on the pea shooter type exaust, new hagon rear shocks, Corbin seat, new wheels with an 18" at the rear and a Dave Taylor head steady as soon as I figure out which version to get: spring or no spring. That is this winters little projects and next winter I want to move to the engine and powder coat the frame and swingarm and tranny cradle, as well as a repaint of the body work.

Lizard King said:
So far I've put on a Magura brake cylinder, single Mikuni, and braided oil lines. I've found that a Sportster gel battery fits rather well. I'm replacing the Boyer with a Rita due to the Boyer's problem with electric starters. I've put on new pipes w/ pea shooters.

That's about where the limits of my mechanical ability kick in.

What else should one do to drag the Commando toward the 20th century? Cam? Big Bore? I've actually seen 2 Dureons on ebay in the last month. Balancing? Blueprinting? Compression? Port grinding? Belt Drives? Transmission?

I'm under no illusion that a 30 year old bike will be able to go head to head with anything coming out of Japan. I just want to get the most out of my machine.

Thanks all.

Lizard King · Nov 27, 2006

I read not to install an 18" rear wheel as it may affect handling

Coco · Nov 27, 2006

Lizard King said:
I read not to install an 18" rear wheel as it may affect handling

Me too, and I heard it was for the better.

Geoffrey Chapman · Nov 27, 2006

I've just started a blog about my bikes at www.geoffsbikes.blogspot.com
I've listed all the mods I've made to my 1971 Roadster
Might give you some ideas

Ron L · Nov 28, 2006

An 18" rear wheel will not affect handling, if you keep the same or similar tire width and height. A significantly wider tire will slow the turn in. This will happen with a 17, 18, or 19 inch wheel. If you are concerned about handling with an 18 inch rear wheel, pick a 100/90-18 tire and it will turn in much like the stock 4.10H-19. Go to a 120/90-18 tire and you will notice a slower turn in with spring rates and ride height untouched. This is of course dependent on riding style. YMMV.

MichaelB · Nov 28, 2006

Geoffrey Chapman said:
I've just started a blog about my bikes at www.geoffsbikes.blogspot.com
I've listed all the mods I've made to my 1971 Roadster
Might give you some ideas

I want to compliment you on your ride. It has evolved over time and you obviously have a passion for it. Nice job.

Captain Chaos · Nov 28, 2006

I just got a Dave Taylor head steady yesterday. Mine came with the head steady PLUS all of the MKIII parts (spring, etc.).

I got it from Commando Specialties on eBay.

Coco · Nov 28, 2006

Captain Chaos said:
I just got a Dave Taylor head steady yesterday. Mine came with the head steady PLUS all of the MKIII parts (spring, etc.).

I got it from Commando Specialties on eBay.

Yes, Duane seems like a nice guy and I am about to order some stuff from them. They actually sell outside of ebay, usually for less than what some of their auctions go for.

Restoring a MKIII. What mods would YOU suggest?

Lizard King

norbsa48503

Coco

Lizard King

Coco

Geoffrey Chapman

Ron L

MichaelB

"Sons of Arthritus"

Captain Chaos

Coco

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