Syscrush wrote:If I did want/need to upgrade to the 16mm pivot bolt:
1. Is there a good source for them, or do I just start calling every one of the usual CBX parts vendors?
2. Does the frame need to be drilled out to take the 16mm bolt?
3. If so, Is it just a matter of drilling, or does some kind of new plug/sleeve need to be welded into the pivot points?
Thanks,
Phil.
16mm swingarm axles are a dime a dozen. If you need one, I can send you one. Tom, Dick and Harry are parting out Prolinks and are selling parts on ebay.
The holes in the 79 frame need to be enlarged to 16mm and also the holes in the footpeg plates on both sides where the axle bolt goes through.
Just drilling or reaming whatever process you use.
EMS wrote:16mm swingarm axles are a dime a dozen. If you need one, I can send you one. Tom, Dick and Harry are parting out Prolinks and are selling parts on ebay.
The holes in the 79 frame need to be enlarged to 16mm and also the holes in the footpeg plates on both sides where the axle bolt goes through.
Just drilling or reaming whatever process you use.
Good to know, thanks. I'll follow up about if I need that bolt from you or not once I know for sure what's going on with this deal.
BTW - those Multistrada forks you have are Showa forks - GSX-R bottoms with radial caliper mounts should fit if one were to wish to swap them. Hmmm...
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
BTW - thanks again to all for the insight & info. The ID on the swingarm pivot bearings was 16mm, not 14. If you fine folks had not informed me about the difference I would have had to take a very disappointing call from my mechanic when I was at my most excited about a long-overdue upgrade! I've decided to go ahead with the 16mm pivot - I said that I don't want to modify the frame at this stage, but I'm fine with drilling out those holes.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
Triumph Tiger 1050 USD forks are 825mm from top to axle centerline (according to seller), and have radial brakes. This isn't confirmed yet, but it looks like they're 100mm spacing and that the Brembo calipers from the Speed Triple should fit and are readily available for non-crazy prices (for Brembo radial calipers, anyhow).
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
steve murdoch icoa #5322 wrote:The 160mm is the distance between the fork leg wiper and the bottom of the tree.
That makes MUCH more sense. Thank you very much.
No way it is traveling that far. A guesstimate of 100mm max.
Now that seems a bit low. Most modern sportbikes are in the 110-120mm range - I wouldn't expect the CBX to be shorter. But with the damping rod fork, maybe it makes sense.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
The Tiger 1050 forks are definitely a contender. Older forks (2007 and earlier) have 108mm spacing on the caliper mounts, while the newer ones have 100mm. I believe that the relatively cheap & plentiful Brembo calipers from the Speed Triple are all 100mm. I have serious doubts about them being any better than Nissin or Tokico calipers, and almost certainly not better than Yamaha's OEM monoblocs, but they're not much more money and that Brembo name on the side looks pretty blingy.
It appears that the earlier measurement given for Duke 690 forks may be off. I reached out to the new owner of my old Duke and he reported that the forks are 840mm long, which would definitely be workable. I'm going to see if I can get out for a visit and to measure myself, and I have also asked another buddy to measure his.
As far as swapping bottoms goes - I have managed to get in touch with a very helpful customer service rep at a company that manufactures aftermarket fork tubes. He says that if I do buy the 690 forks and measure the thread, he will tell me what donor forks would have suitable bottoms for swapping. It's always a pleasure to come across a person/company that is so willing to help. I'm a bit torn about saying the company because on one hand I'd like to send business their way, but on the other hand I don't want to send a herd of would-be swappers their way bugging them with requests for free info.
Anyhow, that helpful person has already provided some VERY important info. GSX-R Showa forks have been 41mm since they went to the BPF design in 2008. I thought that basically all contemporary USD forks are 43mm the same way that just about every sportbike runs a 120/70-17 front tire.
I see the pros and cons of the Tiger vs Duke forks something like this: The Duke forks (if the length is OK and I can find suitable bottoms) are awesome WP forks with the correct travel (so no need for internal mods to the bump stop) and correct amount of slider showing (aesthetics only). On top of all that, they're black with chrome sliders, which fits the look I am going for. The drawback is that getting suitable bottoms is a potentially expensive x-factor. The Tiger forks would need only the bump stop mods and some black coating, but that's not necessarily any cheaper than swapping bottoms on the Duke forks.
Time to double-check that measurement and talk to my suspension guy again...
Last edited by Syscrush on Wed Feb 19, 2014 10:03 am, edited 1 time in total.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
Looking at pics of the fork assemblies from bikes equipped with radial calipers, I'm starting to seriously doubt that it would be possible to come up with a solution that provides adequate clearance for the CB1100F front wheel without spacing the front forks out to an unappealing distance. Here are some pics to give an idea of what I'm talking about:
The Boomies are wide at the hub, and they don't flare in as dramatically as modern wheels. I doubt that they are anywhere near that narrow that close to the axle centerline. It appears that there's something like 1.25-1.5" between the inside faces of those calipers. It's easy to find potential donor bikes to go and measure in order to be sure, but it's really starting to look like it's not going to be workable.
BTW - the Bandit 1200 RSU cartridge forks are ~780mm long, which makes them ~60mm longer than the 'Busa. Very close, but still shorter than I want. It wouldn't be hard to make it work with a custom stepped top triple, but I think I'd go with internals swap on the stock forks before I'd do that.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
Syscrush wrote:Looking at pics of the fork assemblies from bikes equipped with radial calipers, I'm starting to seriously doubt that it would be possible to come up with a solution that provides adequate clearance for the CB1100F front wheel without spacing the front forks out to an unappealing distance.
On the Tiger 1050, the space between calipers is supposedly a bit over 2", so it just might clear. The dream may not be dead just yet. :)
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
Another buddy with a Duke 690 just measured his forks unweighted and says that they're 820mm from top to axle centerline. I'd feel better if his number matched what I got from the guy who bought my old bike, but they're both right in the correct territory, so this fork is definitely a contender.
SuperDuke front ends (with dual front brakes) are less readily available and more costly than GSX-R front ends, but they do pop up now and then. The fork bottoms from the SD's WP forks are a higher-probability fit, so I would probably go that way if I do choose the Duke 690 forks.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
I went to a large local dealership after work yesterday with a vernier caliper, a measuring tape, and a jury-rigged caliper spacing gauge (a 1/4x1" bolt threaded into a 1" long coupling nut - I would thread it out until it just barely fit between the inner faces of the brake calipers, then pull it out and measure it with the vernier), and started measuring.
The Tiger 1050 and Speed Triple with the 108mm mount Nissin calipers have just over 50mm of space between them, which was the largest space that I measured. The newer versions with the 100mm Brembo calipers had more like 35mm, so those are ruled out. The Hypermotard and Hyperstrada were not the same, but both were too small. GSX-Rs and CBRs were also too narrow, but the 2005 ZX-10 was also at about 50mm.
I was very disappointed to find that although they still listed a SuperDuke 990 on their website, they didn't have any in stock, so I couldn't measure that. I am starting to think that it's not likely to fit, though, because everything I measured with Brembos was too narrow. Hopefully I'll have a chance soon to see one in person.
In every case, the caliper starts at very close to 120mm from the axle centerline. So I used that as a basis of comparison for my golden boomerang wheels and took some measurements when I got home.
It looks like the 108mm Nissin setup from the Triumph bikes would either just barely clear or just barely interfere. If it does clear, I might be able to use the Triumph triples, but also might want to go custom anyhow. If it doesn't quite clear, then some custom triples to move the forks ~5mm farther apart than stock should not be a problem.
So it looks like the 108mm Nissin Tiger 1050 forks, resprung and with modified bumpstops are the front-runner if I do decide to go USD.
Phil in Toronto
A cool guy deserves a cool bike, a dork needs a cool bike... Pics of Perry, my '79.
