Replacing Front End

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Thanks Baz,

yep, spring rate seems to be pretty-well right (I've measured deflection under load and it agrees with the standard spring rate). I'd like some more compression damping, but when it comes to suspension, I'm the first to admit I'm out of my depth and need expert assistance. I've put in 10 weight Castrol fork oil this time - no idea what was in beforehand. Seems to be a big improvement. I'll try 15 weight and see what effect that has.

No, I've not tried dropping the forks, it would be a pain to ride if the bars were any lower. Nor any idea on the yoke offset - will investigate.

The master cylinder is Suzuki. The contact patch on the disc is only about 15mm wide. The slave is obviously for a smaller disc rotor. The mounting scares me - always has. I'm thinking about a better caliper and a better mounting. Your axle plate idea is interesting and food for thought. I was thinking of designing some sort of clamp for the fork leg in SolidWorks and getting it CNC machined.
 
If you look underneath your suzuki master cylinder you will see what size it is
If it's bigger than 13 mm then it's probably too big to work effectively (hopefully someone will chime in here with the exact size for your AP caliper)
For example
on my commando I have a 12mm master cylinder and a nissin 4 pot caliper and 320mm disc
It works extremely well
 
davamb said:
One of the bike's previous DPOs stuck what I'm told is a Ceriani front end on my bike and I can't say I'm too pleased with it. In fact it lets the whole bike down. I've been looking into cartridge options as a way of improving matters, but not had any luck so far - the options for 35mm damper-rod forks are basically non existant. Toss in the fact that the disc brake conversion is suspect to say the least means I am now looking around at other options:
  • Buy a used Commando front end. Great, but I've yet to see one come up for sale here and I ran a Wanted ad for some time too.
  • Build a whole front end from parts. Probably expensive, but would mean I could run one of Don's disc-brake packages. Could perhaps still bung cartridges inside just fork tubes, legs and triple clamps.
  • Adapt a complete front end from some other bike. Would still like to keep my cast wheels though. Could also be a cartridge candidate.
Thoughts? Ideas? Other options? There's a great bike hiding behind this crap front-end. Of that I'm sure.
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Gold valve inserts from Racetech. Easy to install in damper rod forks. They don't fit OE Norton forks.
 
oldbeezer said:
baz, where does one get an adapter for the nissin caliper to roadholder fork?
Thanks, Jim
Click to expand...
Sorry I wouldn't know
I make all of my own stuff , I don't think anyone makes one for a nissin
You'd need to make your own or make a drawing or template for someone else to make it
Cheers
 
I'd be pleased just looking at that on a daily basis. Good looking scooter.
 
I'm running Don's damper kit, I just rebuilt the forks a few weeks ago to address a stiction issue. New stanchions with JS turcite bushings. I'm also running RGM alloy yokes with the adjuster nut at the top and a tapered bearing conversion. 12m nissin master cylinder (a retro looking one that looks a lot like the stock commando MC), stock but drilled disc.
 
Do you realise that if your bike feels bad in the front, it is often the rear suspension which is at fault ( damping ) ? I use unmodified Ceriani forks and have never had a problem.
 
When my stock 850 & I were in our younger years and feeling a bit feisty on the back road curves I discovered myself going into the grass at hi speed. I thought the bike had issues until I dialed the rears up all the way. Upon doing this bucking ceased & it would lay into a curve well holding the road as well as stock & ignorance allowed.
Anyway the bike I believe was attempting to straighten up now that more thought is given. Along time ago and memory isn't real clear, but I'm for sure not going to try to duplicate the conditions because no like dirty drawers.
The rear suspension comment brought this on.
 
Thanks guys,

@alcotrel thanks Al, I bought a new set of 7610 Ikons a couple of months back and they improved things substantially. In fact, it was this move that showed up the front end and prompted this whole exercise. I'd got in touch with Ikon to see if my old Konis could be overhauled, but after a half doz emails, I was convinced it would be better value to ditch the (40 yo) oldies and go stright to new. Certainly a better move.

@Time Warp I've looked into emulators and cartridges, but all the organisations I've contacted seem to want serious biccies for the machining required on the forks to take the new gear. Throw in (or out) the weak Aussie dollar and crazy shipping costs and it all got a bit out of hand. I'll have another look at that set. The price is good.

@swooshdave thanks Dave, I'd also looked into putting together a complete front end from bits from Andover and other sources, but again, it came out as silly money. That price for the complete front end is a lot less than the individual bits according to my notes from my investigation, so perhaps worth another look. Yeah, it's steep, but I'm still sitting on my tax return - burning a hole in my pocket.

In the meantime, I bought this kit and have been messing around with it. I can't make much use of the mount, but the caliper is a huge improvement over the old one. Just not enough hours in the day and I'd rather be riding than spannering at this time of year.
 
YSS make an emulator that is similar to the Racetech one and is quite a bit cheaper. I fitted them to some 35mm Yamaha forks without any major engineering work.
 
"If you look at the way some early race bikes were converted from drum to disc with a plate that was drilled for the axle to pass through
And the other end clamped to the slider,or bolted to the torque arm/mudguard bracket to mount the caliper"
Exactly- wouldn't be difficult. Remove any chrome on the disc (sulfuric acid) and resleeve or hget a 12mm master cylinder. Beautiful bike and color!
 
I really like the Kiwi valves-being able to adjust the compression and rebound is perfect. The emulators in my Betor forks made it much more plush with plenty of damping throughout the travel. If you don't want to raise the fork legs to lower the front end you can also raise the rear with some brackets. In your photo of the bike the front end looks high. I raised the rear end of my Guzzi, helped a bit.
 
Attn Old Beeza

I used Madass140's plate to fit a Nissin 4-pot to my bike. The plate is designed for a 6-pot Tokico. The mounting holes are the same but I had to modify (butcher) the inside face of the plate to get clearance for the different shape of the caliper - no special tools just a file and grinder. The reason I wanted the 4-pot Nissin was that my son had 6-pots Tokico's on his Kawasaki and they were a problem. In the UK it is a well known switch as the Nissin's are thought to have a better seal design.
 
nortonmews said:
Attn Old Beeza

I used Madass140's plate to fit a Nissin 4-pot to my bike. The plate is designed for a 6-pot Tokico. The mounting holes are the same but I had to modify (butcher) the inside face of the plate to get clearance for the different shape of the caliper - no special tools just a file and grinder. The reason I wanted the 4-pot Nissin was that my son had 6-pots Tokico's on his Kawasaki and they were a problem. In the UK it is a well known switch as the Nissin's are thought to have a better seal design.
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nortonmews, thank you!! I don't have a mill or a lathe (or the skill to use them) but I do have files and grinder.
Jim
 
Oldbeezer
Just to clarify you do need to fit Madass's larger disc as well - but a quality piece of bling!
 
Thanks yet again nortnmews. What size master cylinder are you using?
My apologies for hijacking this thread.
 
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