GS550E Project "Kafebiku"

[Cipher]

カフェバイク so there

[rustywvw]

Very nice work. I should look into rebuilding my carbs next.

[Fjbj40]

Go here http://www.thegsresources.com/_forum...ht=Pilot+screw for help

Started looking at carbs and found three needles broken and stuck from previous owner. I can tell this bike was loved and cared for . If someone has the ones marked with "F*cked" PM me.

[Evo-Jet]

Is got that vibe man haha i definitely dig it

Thank you! I took a peak at your build also and sometimes I wish I went the less involved rout. Your bike looks very cool indeed.

[Evo-Jet]

Very nice work. I should look into rebuilding my carbs next.

Thank you! Rebuilding carbs is a great idea and once tuned should gain you a few more horses.

[Evo-Jet]

Go here http://www.thegsresources.com/_forum...ht=Pilot+screw for help

Thats a good idea. I'll have to give it a go. I already tried the thumbtack rout and failed. This looks more promising.

[thebrandonbeezy]

Thank you! I took a peak at your build also and sometimes I wish I went the less involved rout. Your bike looks very cool indeed.

Thanks brosif! My next gs will be alot nicer, it was basically a free bike and a shafty at that so i was never planning on putting a ton into it. Not that i have anything against shaftys but I'd rather get more involved in a chain bike.

[Evo-Jet]

Got the wheels on. Brought it outside to see how the light hits it. Can't wait to paint the tins.

[steve murdoch]

Looks great, Evo.
A "rolling" chassis is always a big step.
I like the height you are using for the rear end. Not kicked-up or flat, just a slightly raised stance. 13-1/2"?

[Evo-Jet]

Looks great, Evo.
A "rolling" chassis is always a big step.
I like the height you are using for the rear end. Not kicked-up or flat, just a slightly raised stance. 13-1/2"?

Good eye, you guessed it exactly.

[Chuck78]

You REALLY need to fix that frame hoop error. As stated, 3" or so of shock travel, since the shock is laid down at an angle, is a WHOLE LOT MORE than 3" of rear wheel travel. Hagon shocks will have the proper amount of travel for the bike. A crappy Chinese set of shocks would likely have less travel before shock bottom-out and ride like $#!+ but would keep you from bottoming out the rear tire on the frame at high speeds, which could potentially skid the back tire and cause you to lose control on the highway and have a very terrible fate...

please do not ride this bike until you have the frame fixed. This is very seriously dangerous. Hitting a big dip in the highway will cause the exact scenario I described unless you got springs for a rider 100-150lbs heavier than you, & then that fancy gixxer front suspension is just worthless with a rigid "cafe" type rear hack job.

Sorry to be brutal, but I am very concerned about this, as it looks like you had the frame painted or worse, powdercoated, without fixing the dangerous "accidental rear tire lockup" mistake.

The bike will ride like a dream with proper rear travel, and a proper geometry up front that involves getting the right triple clamp offset made to give you proper trail, based on front tire installed radius and as-the-bike-sits frame head tube rake angle. That's the other terribly grave mistake "cafe" builders make, is they have no concept of suspension geometry, & just run the triples that physically clamp to the modern short USD fork tubes in whatever stem/bearing configuration that they can make bolt to their frame; the bikes just end up with fancy brakes and cartridge fork but handle worse than a stock 1970's bike because the amount of trail generated by the minimal offset modern triples does not work with the rake of older frames and taller than 120/70-17 front tires.

If you put massively tall rear shocks on a vintage bike with a modern triple, taller 17" rear tire, & shorter forks (corners like $#!+ because you can't lean without scraping exhaust and footpegs), & a shorter 17" front tire, you can get the bike back to slow-ish stock steering trail figures, but nothing like what's possible in terms of a sporty racer feel with proper triple camp offset. Hopefully cognitive has some options on Hugh dollar triples in longer offsets for 28 degree rake frames, as the gsxr was somewhere around 23.5-24.5 degrees rake. Requires far less triple offset.

I hope this isn't too much for you, I don't mean to dissolve your build, if looks rad, but I wish I could have spotted this ahead of time to help enlighten you on the common "cafe" mistakes...

Email me if you want any more in depth help. Again, not trying to **** on you, but wanted to inject some critical building feedback in there before you end up with a machine that never meets its handling potential, or worse, is very ill handling. The worst that can happen with the front end is you won't be able to lean very far without scraping, and it will steer very slow compared to its real potential. The rear end is the really critical part

[Chuck78]

550 frames are fairly short length, & I usually sit halfway back into the passented area...sooo... I suggest you extend the frame several inches, leave the nice tail job as is, & extend that seat length several inches. Adding a kick up in the "hoop" would be best while you're welding on it again, as DOHCbikes did. Much better build design and functionality that way...

And look into triples that fit those forks but have more offset. Weiss Racing or my bud Matt Esterline can machine you some custom spec triples. You need to know front tire diameter, & frame head tube rake as measured with the bike fully weighted down. Then you can plug the numbers into an online rake and trail calculator and figure how much offset you need to get 3.8-3.95" trail (a reasonable sporty amount). I'd defer back to 335mm shocks max (that's +10mm over for a stock 750, 550 is shorter even) before figuring up the custom triple dimensions.

with those tires and forks, and proper geometry, the bike will handle like a dream. A true racer.

oh...one other thing. 550's get some wiggle in the frame when taking high speed curves...they are missing a piece of frame facing that the 450/650/750/all bigger bikes got. They need am angled tubular brace on each side of the frame spine from the center spine back downward to the left and right upper cradle tubes, this would be located right behind the ignition coils. Adding this bracing here makes them much more predictable and crisp in turns. The early 400's and 550 frames did not get this but the 750 did, same years even.

[Evo-Jet]

I am afraid this one will be this way. If it really sucks I can source another frame and build it as a true racer. I really do appreciate the input and the suggestions and will definitely use this info on the next build. Worst case is this will be a thread know as "he build a great looking bike that had potential but it handled like crap so learn from his mistakes".

[Chuck78]

No need to source another frame, this one is still easily modifiable. There's still plenty of time to make the corrections. You'll be happy that you did it when the bike was still in pieces.

The massive 350mm shocks should boost your steering performance quite a bit but will give the bike a higher seat height and very downward sloping rider position.
Everything else on your bike looks fantastic however, but I wanted to try and interject some feedback that could help you save it from a few fundamental/common "cafe" mistakes.

Best of luck finishing it with ease. Hit me up any time if you need any brake/suspension/geometry/carb-engine tuning/electrical advice.

[Chuck78]

By the way I think I recall aftermarket exhaust & crappy emgo pods on a gs550 stock bore running around 102.5 mains on the 1st engine (135psi compression) & then the 2nd (7000mi) engine I can't remember if we went up or down in size due to higher compression on the low milage engine. Slide needles went 1 or 1.5 (shimmed with .020" washers) higher than stock (clip goes in lower position to raise jet needle higher for more fuel / less restriction of needle jet). Try that as a baseline but don't settle on it until you've done some full fledged plug chops at full throttle until it's just right & not too lean (danger! Don't melt those sweet pistons), then after getting the mains dialed in, do plug chops at half throttle.
Make sure you fully understand plug chops. Hold throttle in that position and run in through a few gears under load in a desolate area, then hit kill switch/pull in clutch/ close throttle all simultaneously. Coast off the road, let engine cool a few minutes, pull 1 or more spark plugs, swap in some others, ridea home and literally chop the threaded portion off the plug to view the entire insulator. If the mixture is near perfect, there will be a 10 ring at the bottom 10 or 15% of the porcelain insulator. If it's slightly rich, the ring will be higher up or darker brown or black. If it's a good bit rich, there is no need to cut the plug to tell, but when it is near perfect, you will need to chop the threaded portion off to read it.

& read up on swapping on a "Polaris 4012941" regulator rectifier used off eBay for $45. 10,000 times better than stock.
Also I highly recommend an ignition relay be added. The "coil relay mod" is a vast improvement that is very popular across all makes of vintage bike enthusiasts.