Hi my name is Rob form sunny North Queensland in Australia. A couple months back I told my Dad (who loves to restore old dirt bikes) that I would one day like to get an older Jap Bike to turn into a café racer. While trading dirt bike parts he found a Suzuki GS425, picked for next to nothing and gave it me. I plan to do all the mods myself and teach myself along the way so if any has any tips for me feel free to shear them. Here is a picture of what it looked like when I got it .
1979 Suzuki GS 425 "Big Bird"
- Thread starter GronzDog
- Start date
While looking around the web for parts I have noticed that all the 79 GS models from the 550 up have twin disc brakes on the front and a single disc brake on the back. Does anyone know if the swing arms on the GS models are interchangeable along with the head sets/forks? If anyone has a 79 (or around that time) GS 550 or up could they please send me the dimensions of the swing arm linkages so I might be able to compare them to the 425. I would really like to make this mod as I believe that if you want to go fast you need to be able to stop fast.
Big R
Heaven is so far away.
The front end is an easy swap. Find a list of steering stem diameters, and compare your bike to just about EVERY Suzuki ever made......and you'll see what I mean.
A disc brake conversion in the rear though.....not quite so easy. I don't think you'll find anything that drops right in. And if you did, you would still need to setup up the brake pedal. Not impossible, but not nearly as easy as the front end.
A disc brake conversion in the rear though.....not quite so easy. I don't think you'll find anything that drops right in. And if you did, you would still need to setup up the brake pedal. Not impossible, but not nearly as easy as the front end.
I finaly got the bike stripped right down to just a frame so Im going to start chopping and welding the frame to what I want. I have also been looking into a rear disc break convertion and have figured the best way to do this is to swap the hole swing arm out with somthing from a 500 up. The linkage where the swing arm connects on is 200mm long and outer diamiter of about 33mm and inner diamiter of about 22mm. The rear shock mounts 430mm from the rear linkage. if any one out there has a GS 500 or up can you please check these mesurement agains yours so I can see if this convertion is possible
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So I decide to take some time of work and studing uni to have a good go at 425 this for one day this week end. I got rid of anything that wasn't needed and started mods for the tail of the bike. To get a nice bend on the back of the bike i had cut out a peice of the frame then heat the pipe to bend it up. I pritty much ran out of time there so now to finish the rise in the tail I have to cut up some metal tabs and weld them in. This should be fun as it will be my first time mig welding. I also ordered a some new blinkers and a stop/licence plate light so as soon as these arrive i can bend the end of the tail around to finish it off. After stripping the bike it feels good to see that its starting to look like a cafe racer
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buzznichols
Been Around the Block
Big Rich said:
BigSherm posted a really useful resource for fork swapping, under the heading "Great info source for matching steering stems, fork swaps." Use that, and you'll find a ton of front ends that are easy matches. Happy hunting!
Thanks for the help guys I have been on GS resorces but I cant find any where they have swing arm sizes.
So i got a little bit of time this weekend so i cut out and bent up some spacers to fill the gap I had to bend the tail end and welded them in. So maybe next weekend I might be able to grind te weilds back so you wont see that its been modded.
So i got a little bit of time this weekend so i cut out and bent up some spacers to fill the gap I had to bend the tail end and welded them in. So maybe next weekend I might be able to grind te weilds back so you wont see that its been modded.
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So with the first semester of uni finished and some spear time up my sleeve I finally got time to work on my bike. I have bent up the tube for the rear of the bike and welded it on and made the mold for the fibre glass cowl to be made from. I’m going to talk to some friends to see if it’s worth fibre glassing myself or just paying someone else to make it.
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Z
Zookrocker
Guest
What happened to this thread?? it was looking so cool....
Sorry man the build is still going on I've just been bogged down with my wedding uin work and renovating my house. The good news is my wedding done, my house is almost finished and uin is over for a few months at least.
As for the bike I have had some progress. I found a 81 gs650 in a wrekkers and bought the compleat rear end off of it. All I need to do now is trim about 10mm off the swing arm get some new bearings and it should bolt straight on. With my birthday and christmass coming up hopefully the wife will buy me the front end off the 650.
I have also picked up a cheep set of rear sets from china so I've got a little bit of chopping then I can weld some tabs on for them.
Once this is all done I can start working on the motor and reassembliy
Photos soon to come
As for the bike I have had some progress. I found a 81 gs650 in a wrekkers and bought the compleat rear end off of it. All I need to do now is trim about 10mm off the swing arm get some new bearings and it should bolt straight on. With my birthday and christmass coming up hopefully the wife will buy me the front end off the 650.
I have also picked up a cheep set of rear sets from china so I've got a little bit of chopping then I can weld some tabs on for them.
Once this is all done I can start working on the motor and reassembliy
Photos soon to come
Z
Zookrocker
Guest
Cool man! I'm glad this is still one is still goine. From the mock-up with the tank and foam rear section, it looks like its gonna be cool
