Vintage Dirt Bike Q & A

Anything and everything about Vintage Dirt Bikes! After you Register, email nathan@alp-sys.com and let me know so I can activate you.
It is currently Sun Apr 28, 2024 10:24 am

All times are UTC - 7 hours [ DST ]




Post new topic Reply to topic  [ 6 posts ] 
Author Message
PostPosted: Wed Jul 30, 2014 9:58 pm 
Offline

Joined: Tue Mar 12, 2013 4:48 pm
Posts: 47
I was at the track recently and there was a 1978 cr250 with the front forks from a 1983 cr480. Has anyone done this mod? What is involved to make this swap?


Top
 Profile  
 
PostPosted: Sat Aug 02, 2014 3:06 am 
Offline

Joined: Sun Jun 29, 2014 10:52 pm
Posts: 4
working on this myself. The hot setup is to run 1987 (86-88) internals and tubes with the 83 lower legs. You will need to very slightly turn down the bottoming cones - about 1mm smaller. You will also need to have machined a stepped washer for the bottom of the forks - the hole in the 83 fork legs is larger than the 87 bolt diameter. Conversely, you could just run the stock 83 forks with Race Tech emulators.

You will need to run the 83 480 triple clamps obviously. Might have to swap out steering stem - not sure myself on this point yet. Or, Phil Denton sells a nice set of Billet clamps that will bolt right on, but they are pricey!!

You will want to use the 480 hub and brake backing plate - it uses a double arm brake which is stronger. Obviously use the 480 axle too.


Top
 Profile  
 
PostPosted: Tue Aug 05, 2014 10:19 pm 
Offline

Joined: Tue Mar 12, 2013 4:48 pm
Posts: 47
swatdoc wrote:
working on this myself. The hot setup is to run 1987 (86-88) internals and tubes with the 83 lower legs. You will need to very slightly turn down the bottoming cones - about 1mm smaller. You will also need to have machined a stepped washer for the bottom of the forks - the hole in the 83 fork legs is larger than the 87 bolt diameter. Conversely, you could just run the stock 83 forks with Race Tech emulators.

You will need to run the 83 480 triple clamps obviously. Might have to swap out steering stem - not sure myself on this point yet. Or, Phil Denton sells a nice set of Billet clamps that will bolt right on, but they are pricey!!

You will want to use the 480 hub and brake backing plate - it uses a double arm brake which is stronger. Obviously use the 480 axle too.



Thanks for the feedback. I'm currently looking for a complete font end (triple clamps, forks, wheel, hub from a 83) to get started on this.


Top
 Profile  
 
PostPosted: Wed Aug 13, 2014 5:02 pm 
Offline

Joined: Fri Mar 06, 2009 9:58 am
Posts: 11
If you need a set of 87 forks I have some for sale . $100 shipped in US.


Top
 Profile  
 
PostPosted: Sun Jan 11, 2015 10:28 am 
Offline

Joined: Tue Mar 12, 2013 4:48 pm
Posts: 47
sting66cp wrote:
I was at the track recently and there was a 1978 cr250 with the front forks from a 1983 cr480. Has anyone done this mod? What is involved to make this swap?


I'm finally getting back to this, still looking for parts.

Does a wheel / hub assembly from a 1983 cr250 fit on a set of 1983 cr480 forks?


Top
 Profile  
 
PostPosted: Fri Jan 16, 2015 8:28 am 
Offline

Joined: Tue Mar 12, 2013 4:48 pm
Posts: 47
sting66cp wrote:
I was at the track recently and there was a 1978 cr250 with the front forks from a 1983 cr480. Has anyone done this mod? What is involved to make this swap?


Ok, I finally found and purchased a set of 1983 cr480 front forks. I'm looking for a good how to article or video to install new fork seals?


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 6 posts ] 

All times are UTC - 7 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 53 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group