My Mk3 Rebuild is Complete (For Now)

Hi Guys,

Many thanks for the help given me over the past 8 months. My 1975 850 Commando Mk 3 is on the street!






Yes, I know that the handlebars are not standard; they're mild pull-backs to save my lower back,
Yes, I know that the color is non-standard; it's Brooklands Green - I couldn't resist,
Yes, I know that the seat is non-standard; Its a shaved-down Corbin to get my feet closer to the road,
Yes, I know that the rear shocks are shorter, same reason as above,
Yes, I know that the rear wheel is 18", same reason as above.

I do not sit tall in the saddle. When I rode my unmodified 1972 Combat, I was always worrying about which foot to come down on when I stopped. With this sweetheart, I can place both (booted) feet on the ground at a stop, and no longer have these anxieties. The DynoDave starter is a comforting mod as well. It's relieved me of the "stall the engine at a stop light" worries. A touch of the button and I'm ready to go. Us "experienced" riders really embrace all of this recent Norton technology.

Gday Rick, good onya mate! It looks good to me especially the Brooklands Green colour. The mods youve done have made it a good comfortable ride for you and at the end of the day thats all that matters. Regards FOXY

rick in seattle said:

Yes, I know that the handlebars are not standard; they're mild pull-backs to save my lower back,
Yes, I know that the color is non-standard; it's Brooklands Green - I couldn't resist,
Yes, I know that the seat is non-standard; Its a shaved-down Corbin to get my feet closer to the road,
Yes, I know that the rear shocks are shorter, same reason as above,
Yes, I know that the rear wheel is 18", same reason as above.

Click to expand...

Unlike just about many (if not all) British classic bikes, you never need to apologize or make excuses for modifying a Norton. Everyone assumes that any modification was made because the bike is going to be ridden.

Thanks for the picture and great job!

Hi Rick, that bike looks brill !!!!!, I like the way it sits and the gold lettering and stripes look good on the green background. Going to ask a couple of questions, (reason ... also a short person), did you shorten the forks too?, and does the 18" rear wheel alter the speedo ratio?
As said before in this post " it's your bike ", you do with it what you need to to make it yours.... very nice!

That all being said, can we talk about that HORN?!?!? :mrgreen:

Handlebars

Congratulations on completion of your bike , it is a tastefully done machine. Can you tell me about the bars as I have the same problem with neck and lower back, do you know the rise/pullback etc. By the way my Mark III came from Tacoma, WA. and was brought to the south.

does the 18" rear wheel alter the speedo ratio?

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I've found the the rolling circumference of a 120/90- 18 is little different than a 100/90-19, consequently there is very little change in speedo reading . The ratio never changes, regardless what diameter rim or tire size you use. With the lack of accuracy of most Smith chronos, what difference would it make?

Hi Guys,

Thanks for the kind words.

Swooshdave, the horn is indeed ugly. The original was mounted in the same place when I received the bike last year. Moving it to the rear and out of sight will be a winter project. Fortunately, I designed and built the loom myself, and such a modification is easy. I still have the original mounting triangles.

Porterg, the handlebars came from British Cycle, an HD model with a 6" rise, #521-316. I put the identical bars on my BSA victor, and my old 1972 Combat as well. A big relief to my wrists and back.

rbt11548, always a pleasure to chat with a fellow rider with grounding problems like me. The new rear tire is a 110/90-18 Avon Roadrider on a WM3 rim. This tire has a diameter of 663 mm, as opposed to 672mm for the original 4.10-19 Dunlop. This is a 1.4% difference that would overcall a true speed of 70 mph as 71 mph, i.e., well within the speedo accuracy. The wheel change did little, in the end, to lower the bike seat, but it puts a bit more rubber on the road, enlarges my selection of tires, and really looks cool (the old 4.10-19 rear tires always looked wimpy, IMHO, on such a strong bike). I rebuilt the front wheel as well, but to the original specs with an Avon 100/90-19 Roadrider on it. I reduced the rear shocks to 11.9" Hagons, from the original 13". As the shocks are on an angle, the vertical projection is more like a 0.75 inch reduction, so I didn't feel the need to reduce the front fork length. The biggest improvement in riding comfort came from the seat replacement; the original Mk3 seat height was 34", a tough dimension for a guy with a 29" inseam. The Corbin seat was ordered with 1/2" shaved from each side, and effectively dropped 2" from the seat thickness. All told, I reduced the total seat height by 3" , and can now ground both boots when stopped.

Did u specify the dimensions to corbin, or do they make them automatically with the info you provide- i.e. weight, height, inseam? It's been 7 weeks since I ordered mine so I guess it should be coming soon?

Lowering the front end a little would help level the bike and give it more of a sled look.

Pelican,

I specified the 1/2" per side reduction in side padding. This is non-standard, but Corbin seemed happy to do it. The Tech confirmed the change via email prior to building the seat, which took about 3 weeks. The seat is quite wide, and would not have worked for me otherwise.

Swooshdave,

We're practically neighbors here in the PNW. How do I lower the forks?

Nice looking Mk3, BTW.

rick in seattle said:

How do I lower the fork

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hi rick,you could use dominator stancions or cut and machine the ones you have,but you will probably need the dommi internals as well,ie springs damper rods

rick in seattle said:

Swooshdave,

We're practically neighbors here in the PNW. How do I lower the forks?

Nice looking Mk3, BTW.

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That's one of Matt's bikes.

Dunno how to lower the front end but it wouldn't take much to figure out how. I think someone said you start with older Roadholder tubes.

I'll be re-joining NWNO in a bit. Maybe see you at one of the events one of these days.

rick in seattle said:

Hi Guys,


Yes, I know that the handlebars are not standard; they're mild pull-backs to save my lower back,
Yes, I know that the color is non-standard; it's Brooklands Green - I couldn't resist,
Yes, I know that the seat is non-standard; Its a shaved-down Corbin to get my feet closer to the road,
Yes, I know that the rear shocks are shorter, same reason as above,
Yes, I know that the rear wheel is 18", same reason as above.

Click to expand...

Non-standard is not a capital offence my 74 850 is way non-standard (pic on right) but being ridden is all that matters