GL1000/CB900C Fork Tubes
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GL1000/CB900C Fork Tubes
In addition to my '79 GL1000, I've got a fork from a '77 GL1000 which I am fitting to another bike. I know the 75-78 forks do not use a lower slider, and have read that the fork lowers (cases) can wear out, after which they are scrap. My question:
Has anyone used tubes from a CB900C in a GL1000 fork? These tubes are also 37mm but use a lower slider. Is it possible? Has it been done? Are there problems with compatibility that I'm not thinking about?
Thanks,
Has anyone used tubes from a CB900C in a GL1000 fork? These tubes are also 37mm but use a lower slider. Is it possible? Has it been done? Are there problems with compatibility that I'm not thinking about?
Thanks,
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Re: GL1000/CB900C Fork Tubes
I think you have the terminology a little mixed. The slider ( or case as Honda calls it) is the part that holds the axle and slides up and down the fork tube. I think what you are referring to is the slider bearing. The Wing has a top bearing which is not replaceable, no lower bearing. Having said that, the slider lasts for a very long time usually.
The CB900C does have replaceable bearings, but the biggest problem would be the leading axle position, which I guess (since I've never done it) would screw up the handling somewhat. Also I think the fork tubes are longer.
The CB900F might be a better solution.
You could always keep it pure Wing by fitting a set of GL1100 or even 1200 forks.
The CB900C does have replaceable bearings, but the biggest problem would be the leading axle position, which I guess (since I've never done it) would screw up the handling somewhat. Also I think the fork tubes are longer.
The CB900F might be a better solution.
You could always keep it pure Wing by fitting a set of GL1100 or even 1200 forks.
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Re: GL1000/CB900C Fork Tubes
I put a CB900C front end on my 1000/1200 project. Thought about mixing tubes, triples, and brakes, but found that while the tube diameter is the same, the width of the triples is narrower on the 900, and so the threaded axle is too short to use with the 1000 triples.
The 900 triples have different upper and lower offsets, so the tubes rake steeper. The leading axle recovers some of that and makes the trail about the same, I think, but don't quote me. I assume this was all just a styling exercise.
There's no real difference between this one and my stock '77 in regards to handling. Might be just a bit slower steering. The point of the change was to use the newer brake designs.
The 900 triples have different upper and lower offsets, so the tubes rake steeper. The leading axle recovers some of that and makes the trail about the same, I think, but don't quote me. I assume this was all just a styling exercise.
There's no real difference between this one and my stock '77 in regards to handling. Might be just a bit slower steering. The point of the change was to use the newer brake designs.
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Re: GL1000/CB900C Fork Tubes
Thanks for the feedback,
I agree the terminology is not universal. But Honda does not help with the terms they use (eg. CASE, R. FR. FORK (LOWER) 51421-371-003 - or - BUSH, SLIDER 51415-461-003). These are the terms from the Honda parts diagrams for the 1977 GL1000 "right case" and the 1982 CB900C lower "slider" or "bearing", respectively. I've always known these fork parts as tubes, lowers, and bushings.
I'm trying to keep it GL1000 for all the lower-half components (lowers, brakes) because I want to keep the spoked wheel. I thought if the CB900C fork tubes would be a drop-in fit, then it would be simpler than trying to mix/match/space the wheel and brake components between the 1000 wheel and the lowers/sliders/cases from another model.
Since I work at a company with a pretty skookum machine shop, I will probably work with them to build a custom triple. This GL1000 fork will be going on a CB750 sidecar rig. The GL1000 fork has about 10mm less offset than the 750 fork, which will slow the steering. A custom triple clamp will bring the steering geometry back.
Was just checking to see if this had already been attempted by anyone.
I agree the terminology is not universal. But Honda does not help with the terms they use (eg. CASE, R. FR. FORK (LOWER) 51421-371-003 - or - BUSH, SLIDER 51415-461-003). These are the terms from the Honda parts diagrams for the 1977 GL1000 "right case" and the 1982 CB900C lower "slider" or "bearing", respectively. I've always known these fork parts as tubes, lowers, and bushings.
I'm trying to keep it GL1000 for all the lower-half components (lowers, brakes) because I want to keep the spoked wheel. I thought if the CB900C fork tubes would be a drop-in fit, then it would be simpler than trying to mix/match/space the wheel and brake components between the 1000 wheel and the lowers/sliders/cases from another model.
Since I work at a company with a pretty skookum machine shop, I will probably work with them to build a custom triple. This GL1000 fork will be going on a CB750 sidecar rig. The GL1000 fork has about 10mm less offset than the 750 fork, which will slow the steering. A custom triple clamp will bring the steering geometry back.
Was just checking to see if this had already been attempted by anyone.
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Re: GL1000/CB900C Fork Tubes
Gotta love a 'skookum' machine shop ...
Gord
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‘14 KLR650 ... not a rat ... yet
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My Original 'RAT' was a hybrid '82 CB900/1100F
‘14 KLR650 ... not a rat ... yet
‘84 GL1200i ‘R2B6' (Rat to Be 6, the last, adopted by twowings)
My Original 'RAT' was a hybrid '82 CB900/1100F
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Re: GL1000/CB900C Fork Tubes
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Re: GL1000/CB900C Fork Tubes
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"The book is wrong, this whole Conclusion is Fallacious" River Tam
2008 GL1800 IIIA "TH3DOG"
1975/6/7/8/9 Arthur Fulmer Dressed Road bike
1975 Naked Noisy and Nasty in town bike
and a whole garage full of possibilities!!
Psst. oh and by the way CHANGE YOUR BELTS!!!!
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Re: GL1000/CB900C Fork Tubes
Sorry ... fixed ...
G rd
G rd
"I'd rather Ride than Shine"
‘14 KLR650 ... not a rat ... yet
‘84 GL1200i ‘R2B6' (Rat to Be 6, the last, adopted by twowings)
My Original 'RAT' was a hybrid '82 CB900/1100F
‘14 KLR650 ... not a rat ... yet
‘84 GL1200i ‘R2B6' (Rat to Be 6, the last, adopted by twowings)
My Original 'RAT' was a hybrid '82 CB900/1100F
- Sidecar Bob
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Re: GL1000/CB900C Fork Tubes
"BUSH, SLIDER" = slider bush. A bush or bushing is a type of bearing and the slider is the part of the fork leg that slides up & down so Honda does call it what it is.broshae wrote: ↑Fri Jan 14, 2022 11:10 am I agree the terminology is not universal. But Honda does not help with the terms they use (eg. CASE, R. FR. FORK (LOWER) 51421-371-003 - or - BUSH, SLIDER 51415-461-003). These are the terms from the Honda parts diagrams for the 1977 GL1000 "right case" and the 1982 CB900C lower "slider" or "bearing", respectively. I've always known these fork parts as tubes, lowers, and bushings.
BTW: The upper tube is called a stanchion.
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Another guy with two sidecars..... Hmmmm... must be something to that....
The Famous Eccles ('84 CX650EI/VeloUral) winter Never Ending Build (CX500forum)
Click: Colour schematics for all GL1000 & GL1100 and GL1200 standard models plus instructions on how to download the full size version
"A guy with two sidecars can't be all bad." - Cookie
Another guy with two sidecars..... Hmmmm... must be something to that....
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Re: GL1000/CB900C Fork Tubes
In case someone might need them:
I got four NOS sliders and four NOS fork tubes for the GL1000.
Contact me at monaco2021@gmx.de as I do not chime in here often.
I got four NOS sliders and four NOS fork tubes for the GL1000.
Contact me at monaco2021@gmx.de as I do not chime in here often.
1976 GL1000 test mule
1977 GL1000 in parts, rebuild in progress
1969 Ford 17m 2.3V6
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1990 Mustang 5.0 7up conv.
1998 Peugeot 406 Coupe (Propane)
1977 GL1000 in parts, rebuild in progress
1969 Ford 17m 2.3V6
1976 Ford Cortina 2.3V6 (Propane)
1990 Mustang 5.0 7up conv.
1998 Peugeot 406 Coupe (Propane)
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