[boris.h]79 GS 550 / 673cc project

[DohcBikes]

He's using VM carburetors.

I don't see any VM's hooked to that head. Regardless, velocity stacks are a bad idea unless you are a drag racer. And screens on velocity stacks is counterproductive. But I digress, and I will sit back and watch for a while.

Best of luck and most of all have fun. Here's to the Hybrid Club!!

 

[tkent02]

Whoops, Wrong thread.

 

[DohcBikes]

He did originally say he was going to go with vm26's but i think soon realized the nightmare it would have turned out to be. Pretty sure I saw a set of bs32ss somewhere in this thread too, and that's what I would use:-\\\

 

[tkent02]

That's what I'm using on mine too.

 

[boris.h]

Hey guy's!
Just to answer for all, that carbs, on the pictures above are BS32 CARBS, from a gs 850!!! BS34 looked too big for me (I know that I need air velocity toget the fuel in...), and the BS32 are plugged to the head using machined parts, to have 32mm diameter in the continuity of the carbs. The head is machined to have 32mm diameter ports, then they finish, for intake, to 31.5mm valves.
For exhaust, I decided to keep the 28mm valves for costs reasons (and I calculated that these valves are ok until 10500 / 11000 rpm..), but the head is ported to finish at 33mm diameter, just for the continuity with the exhaust: a 650 gsxr one, stainless steel, almost "plug and play", very light one. I'll make some modifications on that one to be able to plug lambda sensors for the carbs settings, and a yoshimura exhaust end....

About velocity stacks, I'll for sure put grids or air filters!!!

 

[boris.h]

So, if that mod says 74hp, I'll wait for more, if I do my job correctly...

 

[boris.h]

I think I'll have few questions:

- jet settings
I think, about main jets, to start, 120 / 125 will be ok for me... what about idle jets and the needle position??? any suggestions?

- ignition plate: I got a gs 850 ignition plate with the rotor. Do you think that they will be ok for me?

thanks a lot!

 

[tkent02]

I think the 850 plate is too big to fit in the 550 engine.

 

[boris.h]

I already got this one and it seems to be the same overall diameter.... will check in february

 

[boris.h]

Maybe, going to get a dyna S, wait and see.
Some pictures of the day.
After having welded the head, I started to reproduce the combustion chamber..

then made the last adjustments between the carbs and the head

and I received the gs 1000 s fork head.

If someone has some pictures or documentation for assembling the fork head on the bike (gs 1000 s documentation for example..)
thanks

 

[Nessism]

That's quite an ambitious project you got there boris h. The expression "all in" comes to mind.

A couple of questions: the GS650 came with BS32 CV carbs, which match the intake ports without all the cutting work. Why did you select the 850 carbs and what is the reason for all the combustion chamber welding?

 

[boris.h]

- about the BS32, I found some BS32 in a perfect state for almost "nothing". I measured the distance between each of them and they fit perfectly to allow straight boots. I machined 4 boots to have 32mm diameter inside them. Standard gs 650 boots have not an inside diameter of 32mm but smaller. Now I have a beautiful "cone" between the beginning of the carbs and the valve, the cone to increase air veloticy inside intake chambers.
- About aluminium welding in one of the chambers, I bought this head with some massive destruction in that combustion chamber, with a lot of bah small holes on the valves seats and, a lot of rust inside the chamber. I removed a lot of material (too much) to get a beautiful surface. So the volume was too big --> aluminium welding and machining again. I still have to buy some valve seats.

 

[boris.h]

ok, here we go! Started disassembling the bike last Weekend!
- Getting the CBR 900 discs today
- getting the ZX calipers tomorrow

- getting the 2 valves I need by the end of next week
- getting the 2 valves seats I need in smtg like two weeks

- started to prepare the gs 1000 s headfork for painting..... looking awesome

I can now push up to try to get the bike ready for april....

About the gsxr exhaust, I realized that I had to remove the central stand to make it able to be mounted, I'll doas this way, some grams removed

 

[boris.h]

 

[boris.h]

ok, so at the moment:
- frame entirely disassembled and ready for paint (black powder coat)
- looking for cheap front zx 750 calipers, bought the discs and fitted them to the front wheel.
- the engine is now ready to be disassembled, put on the operation table between a porsche 911 engine and a clio williams other engine..

Still waiting for the cylinder bloc, I would be interested in the wiseco big bore pistons but I still have to know if they could fit to my swap..

 

[boris.h]

Ok, so with the last Weekend:

- all the black parts and the frame sended to paint. They will come back by the next end of week

- all the engine is disassembled. Cleaning them now....


Next Weekend:
- starting to re-assemble the fork on the frame, the small parts on the frame, the rear brake parts... before playing with the dremel on the cranckcase to make the 650 jugs able to fit. I saw the topic about the WISECO big bore kit and now really interested!

 

[boris.h]

going quickly forward!
- all the engine parts cleaned. I'll keep the old aluminium style, but cleaned.
- all the painted parts even the frame are gone to home. Will start re-assembling tomorrow

About the engine, I'm still waiting for any news from my wiseco distributor

 

[boris.h]

Hi all!
Lot of things done yesterday
- removed the swingarm bearings
- started to disassemble the rear caliper.... wow...

About the rear braking set:
- goodridge line
- EBC pads
- all the gaskets brand new

incomming:
- peinted frame: I want something all "reversible", so even if I won't put again the center stand, and the 4/2 exhaust, I did not cut any part of the frame...
- I expect to receive the gaskets for the braking line and all the bearings today or tomorrow, so I'll be able to put the bike on its wheels by next Weekend!


H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

 

[boris.h]

Let's go!


H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !

H?berg? par Imagesia, le meilleur h?bergeur d'images du net !
I expect the frame, with the fork and the swingarm, all the front face re-assembled.
Next Week, lot of work to do on the head...

 

[boris.h]

ok, so a lot of things done. The frame will be on its wheels next week. I'll also get the gs 1000 s fairing next week and 'll be able to put it on the bike.
Then I'll work on the engine.

Yesterday, some amazing work: How to use a 3D printer for motorcycle stuff?
Some answer -->