'70 stuff

I'm pretty happy with my '70 commando. I've done some stuff to make it better. I've listed some of it, but it's hard to remember everything


add rear directionals
keegler swing arm modification
swing arm oil feed tube
replace swing arm bushings
swap out the 19 for a 21 tooth sprocket
add extra clutch plate
timing chest breather
superblend bearings
bottom end shells (with weep holes)
new .040 over pistons
bored .040 over jugs
head resurface and valve job
new cam bushings
new oil seals
new gaskets
yamabond crankcase assembly
sleeved amals
ammeter headlight mount
rebuilt front forks
'73 disc front brake
bikini fairing
adjustable isolastics
comstock head steady
koni shocks
boyer ignition
dual lead 12 volt coil
steel gas tank
replace brake shoes front and back
new rotor and stator
New kickstart pall/outershaft/kick lever
rebuilt gear box
new rear brake cable
true up spoke wheels
... and numerous stuff that I can't remember

Maybe I could do a few more things like:

rear sets and controls
allow rims or cast wheel modifcation to lighten unsprung weight
swap out early rear hub for a cush drive rear hub
landsdown fork dampers
steering damper

Overall, I'm pretty happy with how my bike runs and handles these days. I do wonder about knowlegable norton owner's opionions of the modifications I haven't done,..... YET...

comments please...

My two penneth on your list of possible future mods:

I sometimes ride my Roadster with US bars and stock footrests and sometimes with clip ons and rear sets. The difference in handling is amazing, it feels like two different bikes. I went for a blast today, the first time with US bars and stock footrests after riding it all summer in cafe racer trim... I frightened myself on a few local fast bends. I had to re-calibrate the brain and slow down a tad!

The Landsowne dampers are fantastic kit and really, really good value for money in terms of performance vs the cost of alternatives (Maxton etc). But they are currently unavailable until John hopefully returns to good health.

The steering damper won't be needed if you use clip ons and rearsets, but might be worth thinking about with US bars and stock footrests (based on my own experience at least).

The Cush drive rear wheel has got to be kinder on the already over stressed gearbox. And, if you want to be kind on your box, you may consider a belt drive and Barnet clutch plates and take a load of mass off of the mainshaft.

Alloy rims look great and are good in theory, so are worth it IMHO, but I'm not sure how fast you would have to ride, or how sensitive a rider you'd need to be, in order to be able to tell any real performance difference though?

Fellow forum member "madass140" makes a direct replacement rear hub with an improved cush drive. Just need to get it laced into the rim of your choice. What pipes are you using?

thanks for your response eddie. I have very low, narrow bars on the bike now that measure 24" across from the end of one grip to the other. Most people look at them and ask how do I steer with them because they are so stubby. I've always liked them myself. When I am not shifting sometimes I put my feet on the passenger pegs which lowers my profile in the wind a bit, but I am almost 6'3" so I have to either duck down a bit or mount a bigger faring if I want to get out of the wind.

I often eye the rear sets I see for sale and wonder if I should just buy a set and put the stock parts in my extra's bin

I recently rebuilt my gearbox and upgraded my layshaft bearing. My bushings and gears were pristine (as was the old layshaft bearing) I only have 20,000 original miles on my bike. It's nice to see my gearbox was really looking unworn, but I am a little bit of a paranoid freak about changing automotive fluids, so I probably change my gearbox lube excessively and shift it gentley like an old lady going to church (with bursts to 7000 rpms...) The gearbox seems pretty solid to me and I was pleased when I disassembled it this summer and it wasn't showing any wear dispite having a chain drive primary and a non-cush hub.

I already have barnett plates I believe... I did them so many years ago... I always look at the price of a belt drive and wince, although I'm sure it takes some of the shock out of the drivetrain. I guess someday I just need to bite that bullet...

I'm surprised that you don't think the alloy rims make a great difference in handling... I always imagined that would make the most difference by removing a large amound of unsprung weight.. I guess that weight is not as much as I imagined...

CJ, I see all of Madass's stuff and drool... He makes some incredible stuff. I have to revisit his improved cush hub and check my wallet...

I have original dunstall decibel pipes. I like them because people who don't see me coming, can't miss hearing me unless they are totally deaf.... It's safer to have loud pipes so I keep them even though they are lookin pretty old at this point.

Thanks for the comments

Hi, I just have a question about one thing on your list: (long list by the way, you´ve been busy... ) "swing arm oil feed tube" ? What am I missing here :? ?
Tommy

o0norton0o wrote:
"I always look at the price of a belt drive and wince, although I'm sure it takes some of the shock out of the drivetrain."

A belt drive is considered to be no easier on the gearbox than a primary chain. I recall an email exchange with Norvil who told me that they always install a later cush drive rear hub in the bikes they were building because the belt drive had no shock absorbing characteristics.

Stephen Hill

Stephen Hill said:

o0norton0o wrote:
"I always look at the price of a belt drive and wince, although I'm sure it takes some of the shock out of the drivetrain."

A belt drive is considered to be no easier on the gearbox than a primary chain. I recall an email exchange with Norvil who told me that they always install a later cush drive rear hub in the bikes they were building because the belt drive had no shock absorbing characteristics.

Stephen Hill

Click to expand...

The benefit IMHO is the massive reduction in rotating weight off of the end of the poor flexing gearbox mainshaft. Achieved via a lighter clutch pack, and alloy clutch basket and lighter belt.

Personally, I have also always been of the strong opinion that belts do not act as a cush, but I still prefer belt over chain because of the aforementioned weight issues.

Another benefit of a belt primary drive is that you can select a higher primary ratio, and revert to a 19 tooth final drive sprocket to avoid increasing stress on the mainshaft.
It also lightens kickstarting effort: less strain on leg and gearbox.

My swingarm oiling tube. Also my spindle reinforcing mod. circa 1983.

Fast Eddie said:

Stephen Hill said:

o0norton0o wrote:
"I always look at the price of a belt drive and wince, although I'm sure it takes some of the shock out of the drivetrain."

A belt drive is considered to be no easier on the gearbox than a primary chain. I recall an email exchange with Norvil who told me that they always install a later cush drive rear hub in the bikes they were building because the belt drive had no shock absorbing characteristics.

Stephen Hill

Click to expand...

The benefit IMHO is the massive reduction in rotating weight off of the end of the poor flexing gearbox mainshaft. Achieved via a lighter clutch pack, and alloy clutch basket and lighter belt.

Personally, I have also always been of the strong opinion that belts do not act as a cush, but I still prefer belt over chain because of the aforementioned weight issues.

Click to expand...

Absolutely!

thank you all for your suggestions and great info.

MFB said:

My swingarm oiling tube. Also my spindle reinforcing mod. circa 1983.

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Click to expand...

Ok thanks for the info, haven´t seen that before. And I don´t have a swingarm anyway, so I just assumed the standard grease version was good enough. I drove the first few years back in the 70:s with the rear suspension, can´t remember having any trouble, but then I got rid of it.
Tommy