Speedo questions about my modded '85 FJ1100

[Moraysan]

Hi, looking for some help here.
I just purchased an '85 FJ1100 and took it for it's first spin today.  LOVE the bike but the speedo doesn't work.
The trouble is that the bike was modded 2 owners ago and I am trying to find a replacement part for the wheels gear unit assembly. I was told that the replacement was an FZ1000 front end (forks and wheels), FZ1000 rear wheel and CB600RR rear shock.
The trouble I am having is that when I search for the part, it looks like the FZ1000 doesn't have a wheel mounted gear assembly. I can physically see it on the wheel but I cannot see it in the parts diagram. I have to assume that the front end may not be an FZ1000.
It's upside down forks and what looks like blue dot calipers.
Any pointers on what I can do to nail down the part number I need?

[fj1289]

Can you post pictures to help?

At least on picture of everything assembled.

Then at least on picture with the front wheel removed - left side of the wheel where the speedometer drive mounts - might have to remove the rubber seal if there is on the gear a better view.

I suspect that someone might have fitted it all with a speedometer drive, but there is no way for the wheel to drive it.

Your solution "might" be to fit a ThunderAce front wheel.  Will have to see the whole setup.  As far as I know, the ThunderAce wheel is the only one Yamaha made with a speedometer driver ve like the older models, but matches the brake type and spacing of the "new" R1 front ends when they first came out.   I suspect the second gen FZ1000 USD forks are the same dimensions.

All this I originally got from a writeup on an R1 fork swap on a TDM85 - but that writeup disappeared 10+ years ago.

Chris

[Moraysan]

FJ 1289, thanks for the quick response. I will take pictures of the wheel/fork combination to see if that helps.
I will be removing the upper fairing tomorrow to see if I can verify that the cable is not the issue.  I don't think it is as I spun the square end of the cable at the wheel end and the speedo moved slightly.
The inside of the wheel gear unit assembly looks like it's rounded out.
If my memory serves me right, the cable can be removed from its sleeve at one end, I am just not sure which end of the cable should be at the bottom and which end at the top if the threads are the same.

[Pat Conlon]

You know about Murphy's Law?
When or if you find a mechanical speedometer drive for your front wheel, you install it only to find your 40 year old speedometer stops working...or starts making the death howl...

Why bother? Why mess around with an old mechanical speedometer when you can fit a new all electric GPS speedometer? No cable, no mechanical wheel drive needed.

Speedhut GPS gauges have been used by several FJ owners.

Aviation Fred is our FJ forum expert in installing these gauges. He will chime in shortly.

https://speedhut.com/categories/gauge-types/led-lighting/speedometers.html

Remember: Murphy was an optimist.

Cheers  Pat

[red]

Moraysan,

+1 on the GPS speedometer.  You can get digitals, swinging needles, digital needles, in round or rectangular form factors.  Some even have odometers and trip trackers.  Amazon has digital GPS speedometers for US$ 30.00 and up ('way up).

Feed it with a USB cable, create a mount that you like, and it's a done deal.

[Moraysan]

Pat and Red, thanks fr the info and link. If I get no joy in solving the problem with the existing equipment, I will look into the digital speedo.
Unfortunately, I'm a bit of a perfectionist, which drives myself nuts 🤪, so having a speedo in the instrument cluster, which does nothing, would annoy me too much. If one of the Speedhut gauges can replace the original in the existing cluster that might also be an option.

[Pat Conlon]

.....If one of the Speedhut gauges can replace the original in the existing cluster that might also be an option.

That's what happens, out comes the old mechanical speedo, in goes the new GPS speedo.

Read all about it:
https://fjowners.com/index.php?topic=16670.0

[aviationfred]

The Speed Hut that Pat speaks about are IMO the way to go. GPS speedometer that is super accurate, the matching tachometer and fuel meter use stepper motors for long life and accuracy.
They are not a simple plug and play item. I have built 6 complete 3 gauge sets for myself and a few other FJ owners.


Fred

[Moraysan]

Thanks for all the replies. I like the Speed Hut gauges but to replace the gauges would cost more than half of what I just paid for the bike! 🤪
Below are some pictures of the forks/wheel to see if someone can help with the model of Yamaha they came off. This would be useful information anyway.

[giantkiller]

I put 2008 gsxr1000 front-ends on three of my fjs. I used a digital speedo that uses a magnet and sensor. I replaced one of the rotor bolts with a hex bolt. Drilled the top of the bolt. And epoxied a magnet into it. Mounted sensor to the  caliper bracket. Ran the wire along the brake line. Works great. Cheap.
I don't know how to post pictures on this new forum.

[red]

Moraysan,

Just a consideration; even if you find hardware that fits, the gear ratio of the drive unit may not produce the results that the instrument is expecting to see. In other words, the speedometer may indicate more or less MPH than you are going.  Wheel/tire size can be a factor there, also. 

Speeedhut is one good option, but there are many good options to pick from, for your new GPS speedometer.

[Pat Conlon]

That looks like a 1992 FZR1000 USD front end just like I used to have on my '84. (Except mine is polished and yours is painted black) The tell are the wings on the fender. Measure the axle diameter, it should be 17mm. On the left lower fork leg there should be 2 nubs that hold the speedo drive in place.  Your picture is unclear, but it looks like there is a black speedo drive on the left side.

[Moraysan]

Thanks for the pictures Pat. I agree that the mods on my bike seem to be like a 1992 FZR1000. Can you tell me if the larger 17in wheels caused much inaccuracy on the FJ1100 speedo?
By the way, that was a tidy bike you had!

[Pat Conlon]

Thanks for the compliment, I still have my '84 but today I have a YZF750 USD front end installed.
No, I did not notice any unusual inaccuracies with the FZR Speedo drive and my FJ speedometer. I say "unusual" because mechanical speedometers inherently have a slight bit of inaccuracy.

Cheers
Pat

[Millietant]

Thanks for the pictures Pat. I agree that the mods on my bike seem to be like a 1992 FZR1000. Can you tell me if the larger 17in wheels caused much inaccuracy on the FJ1100 speedo?
By the way, that was a tidy bike you had!

You definitely don't have a FZ 1000 front end - Yamaha never made that model, so maybe that's why you can't find the parts for it.

Your front end looks exactly like the 1992 FZR 1000 front end that I have on my FJ. Ask of the parts for the speedo Drive are readily available - if you're in the USA, look up the parts on Partzilla - otherwise, Google CMSNL and choose Yamaha Motorcycles, then FZR, then 1000 and 1992 models and Front Wheel. The parts for the speedo are numbered 5, 6, or 11 (depending on which bits are missing) and they're all available (click on each item and you can find the Yamaha part number).

Best of luck