Fork swap

If it's broken or just needs tweaked

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Aussie
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Location: Ashford Kent UK

Fork swap

Postby Aussie » Sat May 24, 2014 2:47 pm

G'day all. I got a 1982 CB650 Nighthawk and a 1980 CB650 Custom. I have a spare Nighthawk front end. Could it be a straight swap onto the Custom as I would like to have twin disc and air forks on the custom as it is my daily ride. Also need to know how much oil goes in them air forks if anyone knows as I lost my PDF manual when my computer crashed and can't seem to locate another.
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Folsoml
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Re: Fork swap

Postby Folsoml » Sat May 24, 2014 4:39 pm

I would measure the diameter of the fork tube. If they are the same size, I cannot imagine why you could not swap them. Fork oil capacity at change is 155 cc per leg. Here is a link to the manual on this site.
Have a problem with your CB650? Have a technical question? Click here!


My Current Bikes: 2005 HD FLHTCUI Electra Glide Ultra Classic, 2007 Yamaha Vino,

cb650
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Re: Fork swap

Postby cb650 » Sat May 24, 2014 6:38 pm

The forks are bigger for the nitehawk. Not a fork swap. Need to swap the triple trees. Then you have to use the stupid nitehawk bars and instrument cluster (one year only). I have a nitehawk and going with a 80 front.
Did you clean the tank out?!?!?!?!

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Aussie
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Location: Ashford Kent UK

Re: Fork swap

Postby Aussie » Sun May 25, 2014 4:38 am

Thanks Guys :wink:

MiGhost
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Re: Fork swap

Postby MiGhost » Sun May 25, 2014 1:32 pm

cb650 wrote:The forks are bigger for the nitehawk. Not a fork swap. Need to swap the triple trees. Then you have to use the stupid nitehawk bars and instrument cluster (one year only).

You can use the 81-82 CB900C/82-83 CB750SC triple tree with the 82 cb650SC forks.
This allows the use of the larger 37mm forks, dual disc brakes, two piston calipers, and still use the standard handle bar, gauges, headlight, and ignition.
~ Ghost

PD50 Carb Info
82 CB650SC Brake Caliper Info

Stable
Wayward Son:1980 CB650C, RestoMod Period Custom Touring
Bad Moon: 1983 XJ750MK Midnight Maxim, Full Dress Tour Deluxe w/ X-1 Fairing
Nemesis: 1983 XJ750K Maxim, Old School style chopper

onepieceatatime
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Location: Franklin County, Pennsylvania, USA

Re: Fork swap

Postby onepieceatatime » Sun May 25, 2014 9:16 pm

Aussie wrote:... Also need to know how much oil goes in them air forks if anyone knows as I lost my PDF manual when my computer crashed and can't seem to locate another.



Image
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

cb650
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Re: Fork swap

Postby cb650 » Mon May 26, 2014 5:58 am

MiGhost wrote:
cb650 wrote:The forks are bigger for the nitehawk. Not a fork swap. Need to swap the triple trees. Then you have to use the stupid nitehawk bars and instrument cluster (one year only).

You can use the 81-82 CB900C/82-83 CB750SC triple tree with the 82 cb650SC forks.
This allows the use of the larger 37mm forks, dual disc brakes, two piston calipers, and still use the standard handle bar, gauges, headlight, and ignition.

Nice to know. I might just keep the forks and lower and look for a 750 upper.
Did you clean the tank out?!?!?!?!

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: Fork swap

Postby onepieceatatime » Mon May 26, 2014 5:49 pm

cb650 wrote:...Nice to know. I might just keep the forks and lower and look for a 750 upper.


I might have one...
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

cb650
Posts: 2959
Joined: Fri Mar 03, 2006 7:20 am
Location: Denver CO USA
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Re: Fork swap

Postby cb650 » Mon May 26, 2014 5:51 pm

cool let me know if you come across it unless the OP wants it.
Did you clean the tank out?!?!?!?!

MiGhost
Posts: 379
Joined: Tue Jun 07, 2011 2:30 am
Location: South Central Mitten

Re: Fork swap

Postby MiGhost » Wed May 28, 2014 12:41 am

cb650 wrote:Nice to know. I might just keep the forks and lower and look for a 750 upper.

I have no way to confirm if the offset is the same between the 650SC, and 900C/750SC trees. You might need to get both upper, and lower.

Still waiting on a couple pieces to do a mock-up, but here is the basic rundown on the parts.

Triple Tree
__________________________________
53230-461-770 BRIDGE, FORK (UPPER)
53200-461-770 STEM, STEERING
81-82 CB900C
82-83 CB750SC

Fork Spacing: 192mm
Fork Tube Diameter: 37mm
Fork Lower Diameter: 60mm

Tarozzi Fork Brace
Fast from the Past: http://www.fastfromthepast.com/servlet/ ... Categories
37X60X192A CB900FB-F2 CB750F 1981-1982 22-0025 (Arched slightly for fender clearance)
37X60X192, CX650 Turbo 1983 22-0015, CX650E 1983 22-0016, CX500E 1982 22-0019

Front Axle
http://scandalon.com/2009/06/motorcycle ... ter-chart/
http://scandalon.com/2009/06/motorcycle ... diameters/
____________________________________________
44301-461-770 AXLE, FR. WHEEL
1981 CB650C
1982 CB650SC
1982-83 CB750SC
1981-82 CB900C

Fork Lowers (Slider)
Note:650SC, and 900C use same lowers/sliders. No issuses with brake rotors/calipers
_________________
51421-461-771 CASE, R. (LOWER)
51521-461-771 CASE, L. (LOWER)
82 CB650SC
81-82 CB900C

Wheel Side Spacer
Note:Have not confirmed which spacer to use.
_________________
44311-461-770 COLR, FR. WHEEL SIDE
1981 CB650C
1981-82 CB900C

44311-460-840 COLR, FR. WHEEL SIDE
1982-85 CB650SC
1982-83 CB750SC

Wheel
Note:650SC, and 900C use same wheel
Still looking for a wire wheel to work with this combination.
_________________
44650-461-771 WHEEL, FR.
1982 CB650SC
1981-82 CB900C
~ Ghost

PD50 Carb Info
82 CB650SC Brake Caliper Info

Stable
Wayward Son:1980 CB650C, RestoMod Period Custom Touring
Bad Moon: 1983 XJ750MK Midnight Maxim, Full Dress Tour Deluxe w/ X-1 Fairing
Nemesis: 1983 XJ750K Maxim, Old School style chopper

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: Fork swap

Postby onepieceatatime » Wed May 28, 2014 9:09 pm

cb650 wrote:cool let me know if you come across it unless the OP wants it.

I found the 750 tree I have, but it is from a 750F, not a C or SC. 37mm forks, ignition mount the same, but the gauge mount spacing is different, so it still wont work correctly to keep original gauges.
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

cb650
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Joined: Fri Mar 03, 2006 7:20 am
Location: Denver CO USA
Contact:

Re: Fork swap

Postby cb650 » Thu May 29, 2014 5:15 am

how far off are they? I could slot the holes or drill a new set. What about the fuse block?
Did you clean the tank out?!?!?!?!

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: Fork swap

Postby onepieceatatime » Thu May 29, 2014 10:14 pm

cb650 wrote:how far off are they? I could slot the holes or drill a new set. What about the fuse block?

'80 cb650
Image

'82 (if I remember the year correctly) 750F
Image

The lower part of the handlebar clamp, on the top tree, is taller by about .5 inch on the 750F than the 650.
The top handlebar clamp, and fuse holder are the same on both (The '82 900F is the same too, but the tree is different)
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE

cb650
Posts: 2959
Joined: Fri Mar 03, 2006 7:20 am
Location: Denver CO USA
Contact:

Re: Fork swap

Postby cb650 » Fri May 30, 2014 7:33 am

You want to sell it? I might be able to figure something out. Aussie you want to try it?
Sorry to step on your post.
Did you clean the tank out?!?!?!?!

onepieceatatime
Posts: 323
Joined: Wed Nov 02, 2011 5:12 am
Location: Franklin County, Pennsylvania, USA

Re: Fork swap

Postby onepieceatatime » Fri May 30, 2014 7:07 pm

cb650 wrote:You want to sell it? I might be able to figure something out. Aussie you want to try it?
Sorry to step on your post.

Sure, I don't need it.
Folsoml wrote: Good judgement comes from experience. Experience comes from bad judgement. :lol:


1977 CB750K
1977 CB750K
1978 CB400A
1980 CB650C
1980 CB650
1982 CB900F
1982 CM450A
1997 GL1500SE


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