Front end swap for Command resto-mod?

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I'm restoring and considering doing some modern mod work to a '72 Commando 750 this winter and interested in successes other builders have had with suspension swaps. Haven't had much luck with Google. My primary concern right now is a front end with a disc setup that will still look cool without being chunky (like most sport and inverted fork setups do). Anything cheaper with stock gold would be cool as well (triple clamps lowers, rims). Maybe an older Honda or Triumph T140? I'd like to keep it looking more classic than modern but am open to ideas.
 
Why not uprate the existing suspension and brakes while keeping it looking somewhat standard, there are quite a few modifications detailed here on this site.
 
Money, mostly. Piecing together a stock disc front end is looking like an incredibly pricey and tedious affair to accomplish something I think I can find complete and cheaper with enough time (I could have grabbed an entire roller for under a grand with a junk motor last month had I known I wanted to do this), but I want this done by spring. I'm having difficulty validating the expense from that angle It's easy to throw a grand at this after lacing a new hub into a wheel, finding lowers, the caliper, disc and master cylinder and everything else. I'm not committed to avoiding it, but am exploring other options. But if I can save a grand + doing something a little interesting and end up with better suspension, that's cool too. If I can find a set of spoke wheels with gold rims that would look nice, you know, just ideas.
 
If you want to stick with conventional forks instead of USD, you have plenty of options, but will still have to deal with things like headlight mounts, fork stops, fender mounts, and so on. Back in the early '80s it was pretty common to swap in the front end from a Ducati, complete with triple clamps, front wheel, and brakes. That gave you larger forks (38 mm?) and good brakes, but the actual damping in the forks was no better than with Roadholders. The triples had less offset, so gave more trail, but that didn't seem to have a noticeable effect on handling. One of my racing buddies did the conversion to his Commando, along with slightly longer rear shocks and dropping the front slightly, and it handled really well. Another conversion I recall from the late '80s was to swap in the forks and triples from a Suzuki Katana, which also gave one 38 mm tubes and a bit more trail. We did this conversion on a friends Commando racer, keeping the Norvil front wheel, brake, and Lockheed caliper, and it was also quite successful. You can see how it looks in this pic of our Norton racer lineup from Daytona in 1990. It's the silver and black Commando.

Front end swap for Command resto-mod?


There's a wide variety of similar forks available that you can fit, and they can be had on eBay for low prices.

Ken
 
You might want to check with our own forum member "madass140" he makes a brake kit that uses a tokiko 6 pot caliper and full floating rotor.
 
I've seen a few cheapo front end changes done and they look just that, cheap. Conventional forks from jappers are usually are painted ,and deteriorated, along with the brake components, and require stripping and painting and/or polishing to look any good. Even then, the proportions are not right, IMO. Easy to get USD front ends with good discs, but they look very out of place on a Commando, just too large in diameter against the front downtube proportions. You may not even be able to machine the yokes out enough, and would then have to replace them as well, and then there are the headlight mounts to consider, and the front guard. So a cheap conversion can end up not being as cheap as you think, or end up just looking odd. if you want a real "special", fine....I'd love one of madass140's front disc assemblies, but I'll be getting some of his rearsets first.
 
I have Yamaha fzr 750 front forks on my commando the yokes are shaped to the commando shape new headlight and clock holders made the same as commando the fork sliders were polished to remove the silver paint etc the stanchions are 39mm the fork offset is only 40mm and this suits me with a 750 frame with a 27 degree headstock .would I ever go back to Norton forks not a chance .......baz
 
For some reason Norton nuts cases not on forums pester me with their joys so share a recent one on a cheap version of Roadholers on early CNW. >>>>>>>>>>>>>>>>

Commando fork damper tubes - MODIFIED
I have some pics taken that illustrate the holes I made and the original ones I blanked off. and drill sizes I used to create a better hydraulic action on my Norton Commando fork damper tubes. I havent gotten them downloaded yet.

My biggest change came from a revalving mod to the inverted cup piston that made a whole world of difference.

Norton's stock damper cap does nothing for the hydraulic effect.... and their inverted cup flapper valve is even less effective at keeping oil pressurized for a slowed damper rod movement

I made one damper tube ( left fork) to act as a Compression Damper retaining some of the up and down movement of the original inverted cup but added a nylon washer undeneath and a brass washer next to the fixing nut to act as another piston ring.

Much better valve action

The rod moves downward more easily... then hits a filled bottom reservoir with about 3/4 inch of travel at a very slow rate before reaching its end. It uses a lighter fork oil, just a bit thicker than ATF. (Its what I had on hand).

The Rebound Damper goes into the right fork and this incorporates a fixed piston.
I sandwiched a rubber washer in between some nylon washers against the inverted cup and tightened down at the end nut. The damper top cap also is improved by fixing a seal in place at the hole in the top cap.

It took about 5 pumps to fill the damper tubes initially , but once they were lubed and some oil filled up the tube's bottom reservoir , you couldnt force the forks to bottom, with the front brake locking the front wheel . because of the hydraulic stop action.

I rode over the roughest piece of twisty 2 lane in the township ..about a quarter mile of rough road and steering intentionally .. into every hole.

As well as it worked, I feel like I can still improve the slider action with a lighter oil selection in the compression side and a heavier oil in the rebound side.

FOr a first effort...I can say it was worth the trouble and the fetching of parts and washer seals that may have cost me $18- $20 which I did not use but only a few of the possibilities I selected to try. The thing is...IT ACTUALLY WORKED...AND PRETTY DARN WELL over some big ass holes.

Additionally... I rode from the cul de sac, in front of my house, over the asphalt berm where it steps down significantly into my yard.... to see if there was any... bottoming clonk .. as before.

It was entirely gone.

Now I have something that will handle the bumps and lumps far better than stock. And I have just begun to adjust the fluid viscosity for a finer fork action.

Tman
"Never tell a zombie he looks like ..Death warmed over"
 

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enhanced pix for a better look, are those suki yokes? why the 900 wheel (guessing for the spokes)? are those custom brake brackets? is the stem 1" diameter & would you know the stem size of the later model gsxr usd forks?
Front end swap for Command resto-mod?
 
The Lansdowne kit and the Madass single 320 mm six pot brake together will cost about $1,000. That seems like a lot of improvement for the money.
I did find the stock brake lacking, it overheated and faded to nothing with hard riding in the mountains. The single disc Madass kit solved that without going over the top (pun)
A modern big double disc on the front of a Commando is a lot more potential negative horsepower than the frame was intended to handle, frame problems could arise.

Glen
 
Biggest problem with Old Norton forks is the fact these are OLD. After 40 years the sliders wear in the center section . Back in the 70's forks where the bottom of the maintenance list . I personally never thought to drain and re-fresh the oil :oops: what few £'s i had was for the pub on a Friday night...well £9 a week wages didnt leave much for bike repairs!
So 40 years on we are left with the worn out machines .. New sliders with modern PEEK bush's will produce forks as good as modern, combined with updated damping and brake up-grades.
 
Upgrading Norton Commando forks with DL1000 forks
http://www.vstrom.info/Smf/index.php?topic=19954.0


can often find whole front ends cheap too
john robert bould said:
Biggest problem with Old Norton forks is the fact these are OLD. After 40 years the sliders wear in the center section . Back in the 70's forks where the bottom of the maintenance list . I personally never thought to drain and re-fresh the oil :oops: what few £'s i had was for the pub on a Friday night...well £9 a week wages didnt leave much for bike repairs!
So 40 years on we are left with the worn out machines .. New sliders with modern PEEK bush's will produce forks as good as modern, combined with updated damping and brake up-grades.
 
84ok said:
enhanced pix for a better look, are those suki yokes? why the 900 wheel (guessing for the spokes)? are those custom brake brackets? is the stem 1" diameter & would you know the stem size of the later model gsxr usd forks?
Front end swap for Command resto-mod?
the yokes are standard yamaha fz750 with the ignition loop cut off shaped and polished alloy (very light) the clock pods i made out of aluminium the headlight brackets i made from stainless steel the front wheel is from an aprillia pegaso its a very light front wheel with a 320mm disc as standard the mudguard is from a hinkley thunderbird the brake calliper is a nissin 4 pot which i made the mount for it has a brembo 12mm master cylinder ,with the yokes on most japanese bikes you just heat the yoke and push the stem out with a press and make a new stem ,the gsxr usd is probably 30mm at the bottom and 25mm at the top,the reason i built my front end like this was mainly cost all the components i picked up at auto jumbles for next to nothing in fact the whole bike was built that way ,i have had my share of standard commando's but i have never ridden one with the lansdown conversion they do sound good ,,,,,,,,,,,,,,,,,,,,,,baz
 
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