GS550L to Cafe Build

[T8erbug]

Awesome. Thanks for the info Toasty. Couple of other quick questions if that's ok. What year is your 550L? I have an 82 550M. I doubt the frames stem changed all that much during the late 70's early 80's 550's. However, just to be sure and for future knowledge, how do you determine the correct bearings when doing this kind of swap?

I saw your brake setup. What parts besides the Honda stuff did you need to finish it off?

Thanks.

Not to snake the question from Toasty but since I'm on here and I can answer a couple for you quick I will. I'm sure Toasty can fill you in on the rest later. When you do a fork swap you just need to measure the inner diameter of the top AND bottom of your stem with the original bearing races uninstalled. Make sure you measure both because many times they are different (so you will need two different bearings). Once you know the ID of your stem (top/bottom) you just need the outer diameter of the inner stem on your desired fork. Once you have that info call AllBalls. I recommend them. Just call up their customer service with your measurements and they will find a bearing that will work if you can't find one easily on their website.
If you want wire wheels on this build I'd suggest starting with a shortened dirt bike fork (seems like a lot of work but trust me it's way less in the long run). That way you can run the dirt bike wheel, brakes, and axle. If I had mine to do over again that's what I'd do.. On my swap I machined hub adapters so I could mate a GSXR600 fork, triumph 320mm dual rotors, and stock 78 gs750 wire wheels together. Luckily I had the friends and resources to do it but I'm pretty sure a shortened dirt bike fork you could do with a hacksaw and some new springs (and I'm sure some other odds and ends). Anyways I hope that may help on some of your decisions. Good luck!!

[Sci85]

Yeah that tells me what I needed to know. I've been wanting to do an UPD fork swap on this bike for awhile now in addition to a GSX 600 motor swap. Sounds like the brake/wheel setup is the hardest part. Thanks!

[Toasty]

After a long hiatus, it's time to finally finish this bike.

I'm going to keep it simple, with less custom fabrication so I can actually get the bike together and running by spring. The GS1100E swingarm will be put aside for now, if I keep the 550 swing arm I don't need to drill the frame or have custom bushings made up. Also, I'll just need the early "E" spacers and 550 wheel bearings for the 750 spokes.

For the engine, I'm just going to use the 550 cams so I don't need to modify my cam gears or modify the timing advance for the 650 cams. I wanted more torque originally but now that I have another bike, this isn't going to be a daily. I just need to torque all the bolts inside the clutch area and time the engine and it's done.

The fairing is going to have to wait too, fabricating a mount is going to take a while. The windscreen is pricey too. I don't have as much money to spend as I did before so the $1,000 fully adjustable YSS shocks are out, I'll pick up another set of Hagons instead.

I still need to finish the wiring but if I get off my butt and just do it, it'll only take another $50 or so and a weekend or two to get done.

Thankfully all the expensive stuff I bought already, I just need a few small bits and pieces and the rotor adapters.

Let the rebirth begin

[Sci85]

Fantastic Toasty! I just recently finished out my 550 to 673 build. I only have a few short rides on her figuring out the jetting. I finally got close the other day and the difference in power is dramatic, especially around 7k rpm. I used the 550 cams but went ahead and slotted and degree'd the cams. These are such fun little bikes. They are so light and easy to flick around and the added power for almost no increase in weight just makes it all the more fun. So, get on it! you won't be disappointed.

[ptexotik]

Looking forward to the evidence!

[Toasty]

Fantastic Toasty! I just recently finished out my 550 to 673 build. I only have a few short rides on her figuring out the jetting. I finally got close the other day and the difference in power is dramatic, especially around 7k rpm. I used the 550 cams but went ahead and slotted and degree'd the cams. These are such fun little bikes. They are so light and easy to flick around and the added power for almost no increase in weight just makes it all the more fun. So, get on it! you won't be disappointed.

Nice! What kind of jetting are you running? Dynojet?

Btw, did you reuse the 550 timing advance and CDI?

[Sci85]

Yes, I bought the dynojet stage III kit for the '82 650G. I am still tuning it so I'll have to get back to you on final jetting. I'm running a mac header with straight through baffle and twin K&N filters. I think if you run the stock airbox, you could probably get away with replacing the 550 main, pilot and needles with the 650 units and be good though.

I am using the 550's igniter but the 650's advance unit. I haven't been able to determine ignition timing yet so not sure how well that combo works other than seat of the pants feel. So far, it feels fine and there's no pinging but I gotta finish the jetting work before I really start playing around with the timing.

Regardless, you GOTTA do this build. I promise you, once it's done and you get a few rides on it, you will think differently about which bike will be your main ride.

What year is your 550?

[wegs426]

Excited to see your build wrap up.
I think you will be more than satisfied with the feel of the 550 cams.
If you decide to do the swingarm swap and want to drill the frame let me know and I'll ship out the cutter for you to borrow. I can give you some tips as well, it's not as difficult as some say and I was very happy with the results.

[Sci85]

Yeah, at some point i would like to do a full suspension swap but it's just not in the budget for now. I'm pretty certain it's a fairly expensive swap. However, many thanks for the offer of assistance and tools. That's really cool of ya.

I finally got the jetting pretty much done. I'm running the original 550 carbs, a 40 pilot (stock for the 550 - the 650 used a 42.5), fuels screws at 3.5 turns out, the stock 650 needle at stock height and the dynojet 155 main with the slide drilled and the air correctors installed. The plugs look just slightly lean but I hear zero pinging with 93 octane so if I change anything, I might richin up the needle slightly. Runs like heck though.

[T8erbug]

Don't sweat the small stuff. Get her on the road and that will be good for now. I do recommend doing the swingarm swap nowish though. I did mine and it ended up being way less of a project while I had the engine out. I drilled my frame and it came out great! Just my two cents. If you're going to have nice forks on it you might as well make that rear end nice to match it! PS you're spacers are done and will be on their way Monday. About time right!?

[Toasty]

So I finally got around to trying out the adapters T8erbug made for me and they work great. My 750 wheel has a broken disc bolt that I need to remove and get the new wheel bearings installed before I can mount them permanently.




I just kinda threw it on there but there is plenty of clearance with the 954RR calipers. They still need to be dremeled a mm or two on the front to fit the disc though.


I bought a used set of motor mounts (lost the originals in two moves) and some 550E axle parts that I needed. Maybe sometime this week or next weekend I can press in the new tapered bearings, after that I just need to get some shocks and I'll have a roller.

[Toasty]

No pics yet but I got some more stuff for the project:

- K&N pod filters (2 into 1 flat kind)
- Dynojet GS650 kit
- gaskets

I have to work Sunday morning but I'll do some wrenching on Saturday. First I need to do the valves on my XT and install the Hyperpro spring (the stock one is total mush now, the shock is okay). I'll get the tapered bearings installed on the GS and hopefully the bearings for the GSXR axle. I watched a few youtube videos and it doesn't look hard.

[Toasty]

Quick update:

I installed the new wheel bearings a while ago but the wheel is slightly off center, gotta send back one of the spacers to have it milled down. Other then that I haven't had much time to work on it, I got the old bearing races out of the steering head (what a PITA) and still need to install the new ones. The old rear shocks I got came in the mail and I got to sit on the bike for the first time, it felt pretty good. The bike sits pretty low so hopefully I have enough ground clearance with the header. I may have to ditch my beat up Mac 4-1 sooner then I thought, the collector is really fat and doesn't hug the frame very well compared to other brands.

I wonder if a scrambler style is do-able

[T8erbug]

Happy to see the parts on the bike! Let's get the spacers fixed up so you can get this baby moving forward.