Been a while since I posted. The slippery slope of FJ mods has bit me again. This spring after browsing Aviation Fred's USD fork mod and following a link on the thread to Marc Rittner's YZF750 USD fork mod... I decided to surf that slope. I had RPM valves in my forks with a superbrace and .85kg/mm springs, a front wheel from an 88 FZR1000 and was generally very happy with the ride and feedback.
But chicks dig USD forks right!
I began in March and was hoping to be completed in time for the Flood Run in April. It took alot more time and money than I had estimated. :dash2: :good2:
I decided to source the bits for the YZF750 conversion and set off to eBay. Long story short I spent quite a bit and am still not completely done but am very satisfied with the results.
It inspires a new level of mid corner confidence that I missed from my FZR days and looks totally bad ass. It really cleaned up the look in front. I now find myself walking around the garage to
view it from different angles. Loving my FJ and this website. :good2:
As I said I was happy with the performance of my old front end setup and am going to post it for sale on here before I take it to eBay.
I will post more pics later, I included one of the day I brought it home for comparison.
Very nice Jeff, I too have converted over to the YZF750 USD forks. My previous forks were the 1992 FZR1000 USD which had no external adjustments for rebound or compression. It took me 2 times R/R'ing the FZR forks, disassembling and fiddling with the shim stacks to get the settings I wanted.
The YZF750 USD's have these adjusters external, but I found the adjustment range on the oem compression needle to be very narrow, so on the advice of Frank (Flynt) I sent the YZF forks up to GP Suspension in Auburn Washington. ( Note: They have since relocated to Oxnard Calif)
They installed their custom cartridges .95kg/mm springs and their proprietary adjusters which have a much wider adjustment range.
I am very happy with these YZF750 forks. I used a top triple clamp from Spiegler for my FZ1 bar: https://spieglerusa.com/controls/handlebar-conversion/handlebar-conversion-kit-4384.htm for an easy plug and play...no need to drill the top triple for the bar clamps.
Is that also what you used?
Well done Jeff.... Mike Ramos will get the word out to the chicks...you'll see.... Cheers Pat
Hi Pat,
So far I am happy with my forks but have not tried to tune much. I am hoping to dial thing in with oil weights, levels and springs. I have a Penske shock in the back but can't remember what spring rate. I think it is on the stiffer side because I thought wifey would ride on back... not so much. I will find out from Traxxion Dynamics, they also helped me with the front spring.
Nice people to work with.
I have 1.05kg/mm spring in front with minimal preload, midrange on comp and rebound as of right now.
Pretty happy with the feel but still have old tires on. Over the winter I am going to measure everything to come up with a base and then get new tires and go "dial it in". I am buying Sport tires this year not Sport touring.
I looked at GP Suspension, not sure what you went with.
Triple clamp wise , I think i got the last set of ThunderAce clamps in the US. I modified them following the link I got to from AviationFreds project.
www.fjmods.uk.MarkRittner2.htm (http://www.fjmods.uk.markrittner2.htm)
Bar adjustments are a little putsy the way I did things but it came out well. LSL superbike bars and 35mm risers from Spiegler.
Have a picture but the PC has the upper hand right now.
He spelled it out quite well and I followed it mostly except for the height you cut off the towers to locate the ignition switch.
I used the relative height of the ignition switch to the bottom of the upper triple clamp to make sure the handlebar lock lined up.
When you switched from FZR to YZF forks, were you able to use your FZR fender?
The YZF fender was one of the hardest to find and most expensive parts of this swap.
Ride on
Jeff
http://www.fjmods.co.uk/MarcRittner2.htm (http://www.fjmods.co.uk/MarcRittner2.htm)
Should have known better than to trust my notes.
Hey Jeff, no the FZR fender won't work with the YZF forks...different fork spacing.
Air tech did my YZF 750 fender...I had my paint shop match the quartz silver on my '84
http://www.airtech-streamlining.com/yamaz/YZF7501993-95.htm (http://www.airtech-streamlining.com/yamaz/YZF7501993-95.htm)
Here is my '84 at the last WCR
(http://www.fjowners.com/index.php?action=dlattach;topic=16939.0;attach=8673;image)
Pat,
Such a shiny bike!
Looks very nice.
I like how the YZF fender scoops air to funnel across the discs.
Thanks for the link, the fender is priced is less than what I paid on Ebay. :Facepalm:
Thanks Jeff, the Airtech fiberglass fender was a bit ragged on the edges so the paint shop had to put a little extra time in to block the edges...I'm happy with the results.
With only a 4 year production run ('94-98) the YZF750 fenders are rare.
I do like how the fender design keeps my stanchion tubes free from bugs.
Cheers. Pat
Your post broke my camels back. My wallet is next. Nice job. :good2: Im accumulating goodies for this mod. Been burning up Pats email, I,m pretty clueless. Can you provide me some details on your brake caliper choice? I've read Marc,s project too.
Mike
Axial mount YZF R-1 monoblocks (gold or blue spots) see your PM, I sent you a FleaBay link.
Looking for a proper FZ-1 14mm m/c for you.
This will be a fun project Mike.....I just love spending someone else's money...bwhahahaha...
just emailed you my cc number :crazy:
Quote from: Mike 86 in San Dimas on November 05, 2017, 09:46:54 PM
Your post broke my camels back. My wallet is next. Nice job. :good2: Im accumulating goodies for this mod. Been burning up Pats email, I,m pretty clueless. Can you provide me some details on your brake caliper choice? I've read Marc,s project too.
Mike
I went with the Blue dots because I already had them on my FJ forks. They seemed to bolt right up to Marc and Pats forks. I had to grind a little bit of clearance on my forks to get them to fit.
I guess Yamaha changed the lower casting a bit. Not sure if you can zoom into the fork that close but I will be happy to take some pics when I get back home. Working out of town this week.
No need. After my post I pulled the trigger on some 2003 YZFR1 units. Only few hundred $ more to go. Then I guess I put this stuff together...somehow. :shok:
Thanks,
Mike
Would I be out of line asking what a ball park figure for the USD fork change might be?
I know what I paid for my GSXR1000 USD conversion. I have no idea what Jeff, Pat, or Tim (Axiom-r) paid. A ballpark figure to budget would be $1000.00-$1500.00.
Look at my GSXR1000 USD write up. There is an itemized parts list with prices that may help with an estimate.
Fred
Thanks Fred, that was great info, I've bookmarked that thread.
that number seems realistic. Assuming you are doing most labor yourself and or slaving some buds. Add some polishing, caliper and fork rebuild and so on, on that used stuff you buy and it adds up. I'm taking it slow just to spread the spending out over several months. Once all the stuff is accumulated and ready to bolt up, I'll try to hijack Pat and Mark for a week end...or two.
If Tina's making lunch....I'm there! Major yum!
Quote from: Pat Conlon on December 29, 2017, 04:33:00 PM
If Tina's making lunch....I'm there! Major yum!
Here's a question for ya Pat. I'm swapping a 91 Fzr 1000 front end onto the FJ. What wisdom can you impart as far as springs are concerned? I'm assuming the stock FZR springs are a bit weak for the extra weight of the FJ. Any preferred brand? Also, were there any mods needed to the fork stops? Any other tidbits of experience would be much appreciated. Thanks, Peter
Hello Peter, The '91/92 FZR1000 USD conversion is the easiest to do....no screwing around with steering stems and the mechanical drive on the FZR wheel plugs right in to your FJ's speedo cable. I followed the info on Barry Edward's site: http://www.fjmods.co.uk/usdforks.htm (http://www.fjmods.co.uk/usdforks.htm)
You are correct, I found the stock FZR springs are a bit light for the FJ. They are .77 kg/mm and I wanted ~.95 kg/mm. I got the Race tech fork springs (see link below) The stock FZR cartridge fork valve can work with the .95 springs, but remember.....
The FZR is Yamaha's de-tuned version of the YZF product line (read: less expensive) Here is the downside of the FZR1000 USD forks....unlike the YZF (or GSXR) forks, there is no provision for external adjustment of compression or rebound. All you have on the FZR forks is a provision for spring preload, so....
I went ahead and bought some Race Tech cartridges and set the compression and rebound via shim stacks on the Race Tech cartridge.
http://www.racetech.com/ProductSearch/12/Yamaha/FZR1000/1991 (http://www.racetech.com/ProductSearch/12/Yamaha/FZR1000/1991)
Once I got the shim stacks where I wanted, I found no need for further adjustment, so external adjustment was not really needed after all..
Steering stop mod was straight forward (you will see) as was the grinding on the FZR top triple for the ignition key barrel fitting. The trick was figuring out how to mount the FZ-1 handle bar. I pressed in steel sleeved rubber bushings on the top FZR triple for the thru bolt on the bar clamps and used back up plates on the underside of the top triple for secure bolting of the bar clamps. I've tried other handle bars, but I keep coming back to the 7/8" FZ-1 bar that has threaded ends for my Vibranator bar end weights (or stock FJ bar ends if you wish)
Cheers Pat
Quote from: Pat Conlon on March 27, 2018, 11:31:50 AM
Hello Peter, The '91/92 FZR1000 USD conversion is the easiest to do....no screwing around with steering stems and the mechanical drive on the FZR wheel plugs right in to your FJ's speedo cable. I followed the info on Barry Edward's site: http://www.fjmods.co.uk/usdforks.htm (http://www.fjmods.co.uk/usdforks.htm)
You are correct, I found the stock FZR springs are a bit light for the FJ. They are .77 kg/mm and I wanted ~.95 kg/mm. I got the Race tech fork springs (see link below) The stock FZR cartridge fork valve can work with the .95 springs, but remember.....
The FZR is Yamaha's de-tuned version of the YZF product line (read: less expensive) Here is the downside of the FZR1000 USD forks....unlike the YZF (or GSXR) forks, there is no provision for external adjustment of compression or rebound. All you have on the FZR forks is a provision for spring preload, so....
I went ahead and bought some Race Tech cartridges and set the compression and rebound via shim stacks on the Race Tech cartridge.
http://www.racetech.com/ProductSearch/12/Yamaha/FZR1000/1991 (http://www.racetech.com/ProductSearch/12/Yamaha/FZR1000/1991)
Once I got the shim stacks where I wanted, I found no need for further adjustment, so external adjustment was not really needed after all..
Steering stop mod was straight forward (you will see) as was the grinding on the FZR top triple for the ignition key barrel fitting. The trick was figuring out how to mount the FZ-1 handle bar. I pressed in steel sleeved rubber bushings on the top FZR triple for the thru bolt on the bar clamps and used back up plates on the underside of the top triple for secure bolting of the bar clamps. I've tried other handle bars, but I keep coming back to the 7/8" FZ-1 bar that has threaded ends for my Vibranator bar end weights (or stock FJ bar ends if you wish)
Cheers Pat
One look at the top triple and it looks like it was designed for rubber mount risers. I want to try to keep the FJ clip-ons though. A quick measurement makes it look possible to weld a 43mm piece of 1/8" wall tubing to the tube cap to mount the clip-on and still be able to adjust the preload and tighten the caps. All depends on having enough meat for a good weld. Haven't got it home yet to do a more accurate assessment.
Please be careful.
The thought of a weld failure while leaned over in a 80 mph sweeper, gives me the heebee geebies.
My opinion of the best method to retain your original clip on bars is to fabricate an adaptor plate to bolt to the top triple clamp plate.
Fairly simple to make if you have the tools to do so. I used 6mm plate steel and some stock tube to mount the bars.
I made some caps out of aluminium to cover the holes in the end of the tubes. . (not fitted in the pic below)
Like Pat, I don't recommend welding tubes to the fork caps.
Regards, Pete.
(http://fjowners.com/gallery/10/536_27_03_18_4_47_11.jpeg)
Quote from: oldktmdude on March 27, 2018, 05:48:41 PM
My opinion of the best method to retain your original clip on bars is to fabricate an adaptor plate to bolt to the top triple clamp plate.
Fairly simple to make if you have the tools to do so. I used 6mm plate steel and some stock tube to mount the bars.
I made some caps out of aluminium to cover the holes in the end of the tubes. . (not fitted in the pic below)
Like Pat, I don't recommend welding tubes to the fork caps.
Regards, Pete.
(http://fjowners.com/gallery/10/536_27_03_18_4_47_11.jpeg)
Yea, I think I'm gonna have to throw in the towel on this idea. I figured a wall thickness of .125 would have been enough meat for a serious weld but figuring an inner diameter of around 1.6", my stubs wouldn't be much thicker than heavy gauge tin foil. Looks like it's back to the drawing board. Thanks for the input guys!
My first thought is to machine new fork caps with mounts for the FJ bars. But not sure I'd want to always be trying to loosen the right fork cap every time I counter steer into a right hand turn...
My latest design for fork extensions. For the Gixxer forks was welding them to the top nut on the forks. Done by a professional extremely good welder and then machined down by a professional machinist. Both. Racers themselves. One is now factory sponsored snow cross racer. Use to be super bike racer. So they know about the stress it's under.
They're clamped by the upper tripple clamp no spinning them off.
Oh and I made bars to mach the fj. With the clamps from the Gixxer clippons. Some 7/8 round aluminum bar. And aluminum rectangular bar.
I made the bars with a Craftsman jigsaw and hf belt sander.
Quote from: giantkiller on March 28, 2018, 01:13:47 AM
I made the bars with a Craftsman jigsaw and hf belt sander.
Next great thought - bear with me here, I just woke up
1. Remove the adjuster from the cap and machine the head of it round. And as small as possible
2. Weld a large (14mm?) aluminum allen head to it to take over the adjusting function
3. This will give back the thickness of the stub and then some. I was losing thickness due to the extra space needed to get a socket in there
4. Machine the stub with a serious bevel for welding
5.Hire somone other than me to lay down some high strength beads
Anybody got a spare set of caps just in case?
Quote from: giantkiller on March 28, 2018, 01:11:22 AM
They're clamped by the upper tripple clamp no spinning them off.
Oh and I made bars to mach the fj. With the clamps from the Gixxer clippons. Some 7/8 round aluminum bar. And aluminum rectangular bar.
That is the essential difference with this design - the extension is gripped by the top clamp. I'd have no worries at all with these.