750 72 Commando restoration help

I am new to the forum and am in the process of rebuilding a 72 Commando. Some basic questions on upgrades and changes for improved performance.
What are the best components in the following areas:
Shocks
Pistons & bearings
cam-upgrade?
Crank
Front forks
Valves and other head components
Ignition
Any other items that would help with both performance and reliability is the area of nearest. I know this will spark controversy, but from your input, I will hopefully get the best collective ideas from a group of those of you with much experience. I want a nice bike to ride iwh any handeling and mechanical upgrades thatr would bresent the best direction.

-One reccomendation would be the crank case breather on the 72. Colorado Norton Works has a nice one that will bolt directly onto your case with not machining needed by using there adaptor plate. ( I currently use one on my 72 and have had no engine or engine to primary leaks )
And aparently there are some others that work well to.

-If you have a disc front, which all 72's do except Hi Rider, and you are looking to keep the original look, you can sleeve the master cylinder to 13mm and use a braided steel break line.

-Don't hook the oil tank breather line to the back of the air box, send it to a catch bottle or a UNI filter, and plug the hole at the back of air box ( if you are keeping original air box ).

-Dyno Daves clutch rod seal is a good and inexpensive fix \ Mod to the clutch.
upgrade the seal to one that wont leak on the outer cover for kickstart and gearshift shafts.

-Don't forget to install a oil filter system if your bike does not already have one.

-Some fork seals are better than others, someone can chime in about that ( I installed ones that came with my bike from the PO, I think they were NOS because they leak, so I will be upgrading this winter ) ANY RECCOMENDATIONS HERE

-CHECK LAYSHAFT BEARING IN GEARBOX!

-Install superblend bearings in the bottom end

-There is some machining you can have done to the oil pump to get better pressure and flow from it, you'll have to search for the thread on here.

-rewire entire bike, 40 year old wiring does not work so well

-Anti wet sump vlave ( lots of controversy here ) some love them and some dont. I dont use one but others have been using them for years and swear by them, worth looking into and develope your own opinion.

-If you go full digital ignition and still want a warning light to function on your bike then you may have to look into a warning light assimilator. Cool kat products has one that works well for a very reasonable price, I believe $20, make sure you get the correct one for either pos or Neg ground.

-If somone is going to relace your front wheel and back for that matter, make sure they know what they are doing when it comes to a norton front disc wheel, it is amongst the hardest wheels to lace properly, there are many stories on here about shops that assure that they know how to lace a wheel and that it will be no porblem, guess what it usually turns out to be a problem, so if the guy says wow a norton, I have not seen one of those since the 70's, you may want to save your self some time and money and just search out a norton guy. ( I believe I wrote a story like that once )

Hope this helps a bit.

Enjoy!

Cheers..... 8)

Wow
Thanks a lot for some great advise. I will post pics when it's done

can-this-box-parts-commando-t13057.html

Here is the link to my resto and the advice the forum gave me on my 72 combat.
It may or may not give you some ideas or answer some questions.

Cheers............... 8)
P.S lets see some Pic's

Great info and thanks again. Also what kind of Tires would you reccomend for all around performance and recreational riding.

jronald@kc.rr.com said:

Great info and thanks again. Also what kind of Tires would you reccomend for all around performance and recreational riding.

Click to expand...

I used the Avons that look like the originals (Avon RoadRiders) for a period specific look ( and they handle well for the street ). but if your not worried about looking original there are many other more modern performance choices of wich the forum members here can chime in on.......... or just search for a tire thread on the forum there are quite a few.



Cheers............... 8)

jronald@kc.rr.com said:

I am new to the forum and am in the process of rebuilding a 72 Commando. Some basic questions on upgrades and changes for improved performance.
What are the best components in the following areas:
Shocks
Pistons & bearings
cam-upgrade?
Crank
Front forks
Valves and other head components
Ignition
Any other items that would help with both performance and reliability is the area of nearest. I know this will spark controversy, but from your input, I will hopefully get the best collective ideas from a group of those of you with much experience. I want a nice bike to ride iwh any handeling and mechanical upgrades thatr would bresent the best direction.

Click to expand...

In the spirit of the question, i.e. upgrades, here's what I went for:

Shocks: Ikon - work way better than OEM replacements, which seem to be under-damped. The Ikons are adjustable for damping and are rebuildable too.
Pistons - Standard stuff is fine, current aftermarket replacements are good, and come with US-made rings. For the serious upgrade (needs new rods as well) have a look at http://www.jsmotorsport.com/
As already said - Superblend main bearings are essential, and the standard layshaft bearing is an accident waiting to happen and needs changing - Mick Hemmings does the best one, from what I can tell.
I used a floating superblend type which is OK but doesn't positively locate the layshaft, and I'll be changing it for a MH version as soon as.
Cam - standard cam works just fine, but for performance there's lots of choices - 2S and 4S cams are still available, along with many others... but it's a big subject!
Crank - standard is fine - if it needs a re-grind make sure it goes to a grinder who can work to the drawing, i.e. .090" radius - anything else and it's scrap.
Forks - as already said, standard seals can be iffy, and the standard damping is poor - I got some Lansdowne cartridge dampers and they're superb, and well worth the investment.
The standard head is OK, and fitting bigger valves requires a whole lot of work to re-angle the valve guides. Pretty much essential for racing, but for a rider? Hmmmm...
Lots of good ignitions, and everyone has their favourite - I'm very happy with the Tri-spark; it ticks over at 750rpm, revs clean and strong - and hasn't caused the exhausts to blue either!
It may be worth considering a belt drive primary, and if you have a front disc it's pretty well essential to get the master cylinder sleeved down to a sensible ratio. beyond this, an aftermarket caliper and larger floating disc is also a good option, and means it can be ridden like a modern bike, rather than an oil tanker!

Also consider new type seals for the gearbox cover which involves machining new grooves. O-ring mod on the tach drive unit will keep it from leaking. IronJohns makes an elegant foolproof switch with a ball valve to stop wet sumping. I have the Pazon SureFire and it's OK, but for almost the same price you can get the PowerArc from Old Britts that includes everything. The circlip behind the clutch locating washer should be replaced with #15 shown here. http://www.oldbritts.com/1975_g12.html 06-8072 This is a much beefier clip and does a good job. Sharp edge facing gearbox. No end of spending your money.

Dave
69S

You guys are all great and your advise is very critical as I like to ride but too late for me to try to be mechanical other than understanding it. Thanks so much
I am thinking about Borani rims 19 front and 18 rear with Avon AM26 110 80s or the same in Excell Rims
Any thoughts

jronald@kc.rr.com said:

You guys are all great and your advise is very critical as I like to ride but too late for me to try to be mechanical other than understanding it. Thanks so much
I am thinking about Borani rims 19 front and 18 rear with Avon AM26 110 80s or the same in Excell Rims
Any thoughts

Click to expand...

Get yourself a fat 16" tire for the back. [Ducks] Just kidding.

thinking about Borani rims 19 front and 18 rear

Get the tyre makers width recomendations , and use wideish one .
Cut the side stand mount off and fit norvil type headers . Better Clearance .