1980 Suzuki GN400 cafe project

[dleekent]

Let me introduce my project:
I have a 1980 Suzuki GN400 bike that my father owned and gave to me 6 years ago. Before I owned it, my father didn't take the best care of her. Not that he trashed the bike, there's just some rust collected on the frame and various chrome parts. We also had to piece the wiring harness back together because some mice chewed it apart. It's never been too reliable. I always had a hard time starting it and it would even die on me sometimes while riding, thus the nickname "Suzi-Q" (Suzi for Suzuki, and Q for questionable). I decided it was time to start this project. I'm no gearhead and this is my first project, so I've been enlisting the help of some friends to make sure that I don't royally screw something up. My goal is to have this bike up and running by the end of summer. My wife would also appreciate it if I don't spend a ton of money. Suzi-Q before I did anything:

 

[dleekent]

First, I wanted to get down to the frame, so, we removed all the guts. This bike really isn't too complicated, so it wasn't too difficult. What I will be doing next is adding a tail loop, stripping the paint, remove rust, and repaint. I've had the bike down to the frame for over a week now, but haven't been able to make too much progress on stripping the paint since it has been too cold and my garage is not heated. I got a little antsy and started the swing arm, but it took all day because the stripper was freezing. Oh well, it's just fun to work on this stuff anyways. I've also cleaned the wiring harness as much as possible. I'm hoping to be able to save it so I don't have to spend money on a new one.

 

[dleekent]

I'm currently looking into purchasing a Mikuni VM carburetor from DCC, but haven't been able to make up my mind on the size. I read a thread where a guy is using a 32mm on his GN400, and another where a guy is using a 34mm. The stock size is 36mm. I've been trying to gather as much info as I can on which one to get, but just haven't been too convinced on which size I should get. Like I said before, this is my first project and I'm learning as I go. Does anyone have any suggestions?

 

[NBraun]

I don't have any ideas on the carb, but it looks like you have apretty good base to start with!

 

[cierrecart]

Just stick with the stock carb. Mine is running fantastic on the stock carb, pod filter and shorty emgo muffler. 52.5 pilot and 155 main jet.

 

[dleekent]

Just stick with the stock carb. Mine is running fantastic on the stock carb, pod filter and shorty emgo muffler. 52.5 pilot and 155 main jet.

I had been thinking of changing mine out for a long time to help increase the performance of it, but I have been questioning whether or not to pay the money after I saw the Holiday Customs build as well as yours a few weeks back still running the stock carb. Maybe the money would be best spent in other places. I noticed that misteroddjob replaced his GN400 with the VM 32mm, but I just don't know what to do right with it now. Unfortunately there just isn't enough info out there on this bike along with good alternatives for the carb, as far as I can tell. It's quite frustrating. Thanks for the info.
I was curious on your tires. My GN400 always felt terrible at high speeds due to the fact that it is such a light bike. I always felt that going 60 was terrifying because I just didn't feel like the bike was really gripping the road. How have you been feeling about your tires, particularly going at higher speeds?

 

[dleekent]

It's been too freaking cold and I have been a little low on money lately, so I haven't been able to make much progress. It's times like these I wish I had a heated garage. Just thought I'd update where I'm at. Me and a buddy went to his parents place to try to fabricate our own tail loop to save a few bucks. After failing miserably, we just decided to stick to stripping the frame. I have the frame paint stripped and wire brushed as well as a coat of primer. I've also cleaned the wiring harness. Looking forward to some slightly warmer weather.

 

[AbbyRider]

Are those the original wheels? I'm not familiar with that vintage of Suzukis but those look pretty sweet for 1980.

 

[dleekent]

Are those the original wheels? I'm not familiar with that vintage of Suzukis but those look pretty sweet for 1980.

They are the stock Mag wheels for the 1980 GN400. I can't wait to replace them with some spoked wheels, but it'll be one of my last purchases.

 

[dleekent]

My old man saved the schematics in microfiche and gave it to me when he gave me the bike. I went to library today and saved them all in pdf form. If anyone needs any individual pages or the full schematics for the GN400, let me know. I'll be happy to share.

 

[dleekent]

I primed all the brackets and the rear wheel today. I'm almost done priming, but this process is taking time. Everything that needs to be painted and primed needed a lot of attention including some minor surface rust to remove. Since I'm holding on to the mag wheels for now, I needed to get them to look right. I like the look of the metal finish on the edges, so I wanted to cover them up before I primed them. It took FOREVER, but I like the simple details. I hope it all looks right when I take off the tape.

 

[dleekent]

While waiting for warmer weather to finish up painting, I wanted to start cleaning up the aluminum and chrome parts, and I've only finished the stator so far. As I was cleaning off the oxidization, I noticed it was really really scratched. I had to sand it in order to get that nice clean look. I've probably spent over 5 hours on this alone and I can't wait to get it buffed, but I'm pretty happy with it for now.

The stator after I cleaned it:

The stator after I sanded it:

 

[dleekent]

Finally got some nice weather yesterday, so I finished painting up the rear wheel. The front one is almost done, it'll just need a good cleaning, then some more clear coat. I had originally planned to replace the mag wheels with some spoked ones, but I'm thinking about keeping them now. I put a ton of work into these and I think they look a whole lot better now. Plus, I wanted to retain a descent amount of the original bike.

before:

after:

 

[dleekent]

I've been spending some time cleaning up some of the aluminum and chrome parts.

foot brake lever before:

foot brake lever after:

left foot rest before:

left foot rest after:

chain cover before:

chain cover after:

front sprocket cover after:

 

[dleekent]

I hit a bit of a frustrating snag today. I've had a few brackets as well as the triple trees painted for some time now, but I noticed that the top triple tree piece chips very easily. Is there anyway to keep the paint from chipping like using some kind of sealer or did I just use bad paint or something?

My process: stripping with aircraft stripper, wire wheeling the rust, cleaning, Rust-Oleum Self Etching Primer, Dupli-Color Engine Enamel paint, Dupli-Color Engine Enamel clear coat. The reason I chose the paint was because of video I watched on painting the frame. I followed all the steps on the cans which including temperature and coating.

I'm too nervous to test out the other brackets to see if they chip as easily just in case there is some way to avoid having to repaint everything. This would include both wheels, the triple trees, and engine mounting brackets.

Does anyone have any suggestions? I need help!!!!

 

[chambers]

Hey man those wheels look sweet! As for the chipping maybe you could try a 2pak clear over top? Might set a bit harder.... I'm not a painter this is just an idea. Keep up the good work

 

[dleekent]

Hey man those wheels look sweet! As for the chipping maybe you could try a 2pak clear over top? Might set a bit harder.... I'm not a painter this is just an idea. Keep up the good work

Thanks for the kind words! Hopefully I won't have to repaint the wheels. I'll look into the 2pak.

 

[dleekent]

I haven't gotten any work done on the bike lately since my wife decided she wanted to build a garden this year and I got sucked in to Game of Thrones (nerd). However, I finally get my tail loop. After failing to make my own, searching ebay, and refusing to pay $80 for one on DCC, I found cafegoose on DTT. He sells them for $50, free shipping. It's perfect.



If you're in need of one, look him up. It's the cheapest price I've seen, and he ships them out fast. Here's his topic page:
http://www.dotheton.com/forum/index.php?topic=34914.msg545952#msg545952

Now it's time to weld this sucker on!

 

[dleekent]

Finally got the tail loop welded on thanks to the help of a good friend. There's no going back now. Next step will be to get the seat made so I know exactly where to weld a couple of brackets. My plan is to try to use the old seat and cut it to the shape I want. If it doesn't work, I'll have to just fabricate my own pan.

 

[dleekent]

I started working on the seat mold. I got the idea for the clay from MotoMadness's page: http://www.dotheton.com/forum/index.php?topic=36776.0. I wanted to make sure I had a good transition from the tank to the seat. Soon I'll be fiberglassing the seat mold, then welding on the brackets.