GS1100g cylinder jug on a 78-80 GS1000

[gsman]

Hi!

Will a GS1100g cylinderjug fit straight on a 78-80 GS1000
crankcase?
Or is it like 750>850 that some metal must
be removed in the cylinder to crankcase area?

In advance
Thanks.

gsman

[tkent02]

I'm wondering the same thing..... Want to make my 750 an 1100. Have the pieces in the garage, I'll try to check tonight.

[Nessism]

Steve (Supertrapp) has a thread somewhere on what he did regarding use of the 1100 cylinder on a 1000.

[Guest]

Yes an 1100G cylinder will directly bolt onto a 78-80 1000 engine. I have one and planning on doing a Wiseco kit. With the 1100G head the cylinders only have to be shaved .5 versus the stock sleeves that have to be shaved so much I was worried about cracking under use.

[gsman]

Thanks!
That was also the rumors that I have heard
that a 1100 jug should should fit on a 1000
without to much hassle.
I also know the 1000 and 1100 also use the same wristpin diameter
of 18mm compared to the 77-79 gs750 16mm so there should be
a lot of piston options.
Some info on the net I was reading said that the actual compression
(for that version) ratio on the wiseco piston in real are lower than the advertised teoretical 10.25-1
mounted and when in use as they sits a little bit lower in the cylinder
at TDC by having the pin a little higher almost touching the lower oilring.

Some say that the MTC brand similar to the wiseco 10.25-1 version
actually have a little higher compression. About 10.5-1 or so
for the mildest version(73mm Bore)
Anyone feel free to update me on this.

gsman

[tkent02]

I just slid my 1100G cylinders down over the 1000 pistons, it went all the way down into the 1000 block without hanging up on anything.

[Guest]

But isn't there a stroke difference? Gs 1000 stroke 64.8 mm, Gs1100 stroke 66mm

[tkent02]

So it will be slightly less displacement than the 1100G was, but it's still a big increase over the 1000 displacement. Taking the bore from 70mm to 72mm is worth doing.

[gsman]

I have also heard that the 1100g crank is a lot stronger
in addition to the longer stroke you guys here
are telling about.
Also interesting,That also means that maybe fitting an 1100g
crank in to the 1000 block(if the 1100g crankbearings fit)
will do the 1000 bottom end stronger.
Anyone who knows if the 1100g crank fit the 1000 block?

gsman

[limeex2]

Steve (Supertrapp) has a thread somewhere on what he did regarding use of the 1100 cylinder on a 1000.

Can you help me find that thread? I am putting a 1100g top.end on a 78 gs1000 in the very near future

[Nessism]

Can you help me find that thread? I am putting a 1100g top.end on a 78 gs1000 in the very near future

You're killing me man. You're sitting there sucking down a beer while I'm searching out threads for YOU! Oh well... http://www.thegsresources.com/_forum...mp-Mikuni-RS34

[limeex2]

You're killing me man. You're sitting there sucking down a beer while I'm searching out threads for YOU! Oh well... http://www.thegsresources.com/_forum...mp-Mikuni-RS34

Sorry no beer at work. lemons in the water though! This person is doing extensive mods. I am would like to put (um, already have 'em...)stock 1100g pistons, cylinder, head and carbs on a 1000 bottom end. Plug and play per say'?

[Steve]

But isn't there a stroke difference? Gs 1000 stroke 64.8 mm, Gs1100 stroke 66mm

So it will be slightly less displacement than the 1100G was, but it's still a big increase over the 1000 displacement. Taking the bore from 70mm to 72mm is worth doing.

1100G stock displacement is 1074.9

1000E (or G) stock displacement is 997.5

A 1000 with 1100 barrels (a 2.0mm overbore) displacement is 1055.3

.

[limeex2]

I am motor stupid! Going There is a difference in stroke of 1.2mm. Wouldn't this result in the piston not rising by 1.2mm thus lower compression? If the answer is no,and to stop worrying, is there a benefit to using the thinner gs1000 base gasket?

[Steve]

Yes, there is a difference in stroke, but only half of that difference is at the top. You will have 0.6mm more room at the top.

Yes, that is just a bit less compression, but how much less would have to be measured and calculated.

.