Project GS1000 with GS1100G D-Port Head, 1100G Cylinder & Mikuni RS34

[srsupertrap]

Last year I started to take an interest in upgrading my 79 GS1000EN engine which was already equipped with a tried & true Wiseco 1085 Kit with Andrews S1 Cams, VM29 S/B and a Supertrapp 4 into 1. Living in Colorado Springs at 6000 feet I have probably lost approximately 20% of my GS's HP & torque associated with with the Big Bore Kit.

What to do? My project goal was to boost street torque so I started reading old threads. I ran across Frankenzuki's thread about transplanting a GS1100G Head on top of a GS1000 2V engine and I that started me thinking. I didn't want to punch out the GS1000 sleeves because at 73mm they were already paper thin. Although there are old threads on the subject what I decided to swap the GS1000 Cylinders & Head and swap them out with the following:

• GS1100G Cylinder and bore it out to accept a set of Wiseco 1100 pistons with a 10:25 to 1 CR
• Top that off with a GS1100G D Port Head w 3 angle valve job & mild street port
• Keep the Andrews S1 Cam which enhance low end punch
• Swap the VM29 in favor of a rack of Mikuni RS34 Flatslides with K&N individual Air Filters

Unfortunately with all projects they take more time than expected coupled with the fact that sourcing the RS34 Carbs became a nightmare with the Japanese earthquake. Fortunately Z-1 came through in a pinch. So follow along as I document this project. I took over 125 pics from start to finish. First, I had to get the 1100G parts which I found on EBay back in late Novemeber . . . Here is those pics that I started with

Supposedly low mileage but corrision was evident by the intake port

Th head I removed was a S-1 model & this one is a S-6 ( last of the breed)

GS1100G Cylinder very beefy compared to GS1000 cylinders

 

[srsupertrap]

Here is what the 1100G Head looks like after degreasing it. Next with the help of Tkent02 we removed the Valves, Springs (trash), Keepers, Retainers and bag & mark everything up for a later day.

With all the corrision evident I felt compelled to have the head bead blasted before sending it out to the Machone Shop which was still an open question back in January 2011. The Head was bead blasted by A&P Cylinder Heads in Arvada, CO for $50

 

[Flyboy]

Wow, this is going to be interesting, I am along for the ride on this one, living up at 5500ft as well, I have always wanted a bit more poke out of my 1000, just to get it back to sea level performance and then a bit, but without sacrificing reliability.

 

[Guest]

Great work man! looking forward to the updates :clap:

Just curious...

1. did you have the camshaft bearings area bead blasted as well, or... ?
2. what are the S-1 and S-6 marks on the head that you're referring to?

Thanks

 

[srsupertrap]

Wow, this is going to be interesting, I am along for the ride on this one, living up at 5500ft as well, I have always wanted a bit more poke out of my 1000, just to get it back to sea level performance and then a bit, but without sacrificing reliability.

+1: My goal was to maintain the reliability of stock so even if you choose to stick with a set of 1100G Pistons & cylinders you will retain the reliability of GS. The above pics show the 1100G cylinder which I didn't use because it had a portion of a fin broken off.

G

great work man! looking forward to the updates :clap:



Just curious...

1. did you have the camshaft bearings area bead blasted as well, or... ?
2. what are the S-1 and S-6 marks on the head that you're referring to?

Thanks .

Psyguy,

Yes the were blasted as well, forgot to tell the shop to make them off. I should have No ill effects yet?. Yeah its running. The S-1 , S-3, S-4 are casting marks that any manufacturer adds to the mold to maintain revision & design control. The S-6 mark I am referring to is shown #3 pic right above Made in Japan. Although I am not 100%, I believe ithe S-6 denotes D-Port shaped exhaust which was introduced to increase the torque of the last of the US GS 2V motors.

 

[srsupertrap]

I also bead blasted the valve cover. As you know the 1100G valve covers included additional bolts to ensure the valve cover gasket did not leak.

Here is the 1100G cylinder I decided not to use because of that chipped fin. Still has the hone marks showing

The 1100G cylinder differs from the GS1000 2V & GS1100 4V in that it does not use O-rings betwenn the liners (No gap) which is illustrated in this pic.

 

[srsupertrap]

Here is some photos of the tear down process back in May 2011. I took advantage of Frankenzuki's sale of 1000 & 1100 performance parts. I bought his set of used Wiseco 73.5 mm (1100) pistons which now power this GS1100. I sent out all the 1100 parts that needed engine work machining back in February . . . way too long turn around time

Start with one perfectly running GS1085, I had everyting tore down to the cases in about 4 hours or so. I sold the GS1000 cylinder & Wiseco 1085 pistons to some guy in Norway. They are probably the only one left with any $$$

Was obviously running too rich even after going to VM29 2.0 slides

 

[srsupertrap]

I stow everything away and out of harms way, throw acover on it and call it good

Here is the old engine parts: The head has 44K on it Still have the Cylinder head, Cam Bearings, Valve Cover, Buckets etc
Reused the Cams, Tensioner, Cam Chain guides & Bolts

 

[srsupertrap]

Now I was ready to see for myself whether that 1100 Cylinder would slip into the GS1000 cases or not. I was NOT looking forward to using an air grinder but the proof is in the pudding

I drop it over the Con Rods and it drops straight down, contacts the case and then turn the crank over & over till my arms
hurts and oil finally starts coming out from the oil cooler lines. No Form, Fit or Function issues

 

[cowboyup3371]

This has been some good reading Steve. Looking forward to more.

 

[srsupertrap]

Thanks cowboyup3371

I decide back in February to send my GS1100G cylinder head & cylinders to Tom Kleeme in Daven port, IA. Here is the website

http://www.klemmeperformancemotorcycle.com/

Look most knowledable builders he knows the GS1100 4V inside & out but does not due a lot of GS1000 or for that matter GS1100 G Heads. Tom has built Tripivot old GS1000 2V motors and after speaking with Tom & Trip I know he is my guy. Tom still does a lot of KZ1000 2V J Motors for drag racers. I am not interested in drag racing but I do want quality work so I order the following Work Order:

1) 3 Angle Valve Job on 1100G D Port
2) Clean up the Intake (Street Port) Ports
3) Bore the Cylinder to match the supplied Wiseco 1100 pistons
4) Radius the bottom of #3 cylinder liner ( This was not needed and based on incorrect information from another thread but caused a lot of confusion & delays )

I ship off the parts and wait

 

[srsupertrap]

I get my parts back from Kleeme Performance but check out the photo date stamp. I have lost a lot of time

I decided to use a different cylinder due to the chipped fin in the Black One shown previously

 

[John Kat]

Can one use only the cylinder from the GS 1100 and keep the standard GS 1000 cylinder head ?

 

[srsupertrap]

Can one use only the cylinder from the GS 1100 and keep the standard GS 1000 cylinder head ?

Yes, The bolt pattern is identical on the GS1100 & GS1000 2V are the same. On second thought, the 73mm cylinder bore mated to a 70mm Combustion Chamber might result in some strange combustion results . . .

 

[srsupertrap]

Next, I paint the Head & Cylinder so I start the tedious taping process off.

 

[John Kat]

Yes, The bolt pattern is identical on the GS1100 & GS1000 2V are the same. On second thought, the 73mm cylinder bore mated to a 70mm Combustion Chamber might result in some strange combustion results . . .

For sure, but no more than the oversize piston kits I suppose?
I wonder if the design of the pistons differs between a std GS 1100 and say Wiseco pistons?
In general it's good design practice to have a squish area on the surround of the piston.

 

[srsupertrap]

For sure, but no more than the oversize piston kits I suppose?
I wonder if the design of the pistons differs between a std GS 1100 and say Wiseco pistons?
In general it's good design practice to have a squish area on the surround of the piston.

Yeah, you are right about the Wiseco piston kits.

I have the set of GS1000 9:2:1 ART pistons they appear to very samiliar to Wiseco 73 & 73.5 mm pistons. I think the Wiseco's crown is bit higher :?:

 

[srsupertrap]

Based on Sharpy's & Isleoman's recommendation I paint the cylinder head & cylinder with VHT SP127 Universal Aluminum

I purchased three cans of VHT and barely used 1 1/2 cans between the parts shown

Next, I bake both per the instructions

 

[srsupertrap]

Next I start assembling the Valve components in the 1100G Head. I decide to go with stock Suzuki valve springs because the Andrews S1 cam is a mild grind. I won these NOS set from a guy in South Africa.

I get lucky and the GS1000 tach drive assembly slips right in too.

Next I install the OEM retainers, install new OEM valve stem seals and start installing the 1100G buckets. I install assembly lube on those which do not spin around easily

 

[srsupertrap]

Next, I installed new carb boots, with O-rings for the larger RS34/CV Carbs

Next prep surfaces for new (Used) 73.5 pistons. I remove the oil from the gallies with a syringe to avoid contact with gaskets. Wish I could have painted the cases