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Biggest bore on a GS1000 ?


FJD

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On 1/25/2020 at 2:41 PM, Reinhoud said:

1100 rods are 1.5mm longer than 1000 rods, 78mm on a 1000 crank will give you 1238cc, 78mm on a 1100 crank will give you 1260cc

No one mentioned 1100 crank! So as I said, 78mm bore is 78mm bore and capacity only changes via stroke - not rods!

Edited by Gixer1460
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4 hours ago, Gixer1460 said:

No one mentioned 1100 crank! So as I said, 78mm bore is 78mm bore and it only changes via stroke - not rods!

I thought I just give some additional information.. ;) I saw the number 1260

Edited by Reinhoud
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On 1/25/2020 at 5:54 PM, Gixer1460 said:

No one mentioned 1100 crank! So as I said, 78mm bore is 78mm bore and it only changes via stroke - not rods!

Correct I personally never mentioned changing the Crank or rods thus i still say 78mm equals 1238cc and not sure why you previously posted mixed quotes :(.

But now all has been explained in another post i will guess all is understood 1238 difference to 1260. 

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On 1/28/2020 at 8:08 AM, kiwi said:

Correct I personally never mentioned changing the Crank or rods thus i still say 78mm equals 1238cc and not sure why you previously posted mixed quotes :(.

But now all has been explained in another post i will guess all is understood 1238 difference to 1260. 

Sorry for any confusion 1100 crank would be 1260. 1100 rods on 1000 crank 1238. Sorry if I confused anyone. 

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  • 2 weeks later...
On 11/29/2019 at 11:05 PM, GSX1100dreamn said:

Here is a 2 valve head motor,

GSX crankcase prostock motor.

2098910966_VinceandHines1655ccProstockmotor7.25@187mph..thumb.jpg.a54367a8ff42d1b8a3c4c0a41dc33c84.jpg

At the time 1655cc 18:1 compression 300-350 hp 50mm intake valves 50mm lectrons.

They now run 1800cc

The guy who builds these motors Peter Allen built my 1260.

Not much help but 2 valve porn.

Cheers Andrew.

 

Those 50mm intake valves

IMG_1140.thumb.JPG.9801024c1d747621cb8860b0f28b3e9d.JPG

1340705918_IMG_1140-Copy.thumb.JPG.03fdcfec8c8588821c04a52662ce0901.JPG

Cheers Andrew.

 

Edited by GSX1100dreamn
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  • 2 months later...
On 2/12/2020 at 8:00 AM, Reinhoud said:

I installed the cylinders today.

 

How is the bike of the TS going?

big bore.jpg

Reinhould are those liner top lips breaking into the camchain centre seal location area ?

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13 hours ago, kiwi said:

Reinhould are those liner top lips breaking into the camchain centre seal location area ?

I think so, but there's a bit taken off, the photo's I have aren't clear.

The O-ring fits in as per normal, if that's the question.

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It's weird that the vertical plugs look like they are 'designed' to be there in the chamber, only when you look at the top side do they look odd!

50mm valves - THATS BIG O.o :tu

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  • 1 month later...
On 11/29/2019 at 8:37 AM, Cheeky4648 said:

@FJDif it is a gs1000 8v? Block it will give you roughly 1240cc @ 78mm. Imo it’s on the limit and will have very thin liners. I considered doing this but for my road bike I went with 76mm Kawasaki Pistons from Mtc. Even using gs1100efe liners I had to hand relieve the crank cases. Using any liner that is bigger on the od than a efe liner makes the block very weak and will window out into fresh air between the cylinders, with that you get oil leaks and a very unstable block with which ring life will suffer. 

I fitted new liners when I went out to 78mm. Had no issues. I used custom Wiseco pistons bought through Dynoman.com. 150 hp at the rear wheel. Very nice power too!

IMG_2527.JPG

IMG_2692.JPG

IMG_2655.JPG

IMG_2657.JPG

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On 5/1/2020 at 12:55 PM, Reinhoud said:

I made the head of my GS1000 a twin spark.

 

 

Twin Spark Bottom.JPG

Twin Spark Top.JPG

Kop.JPG

Has anyone ever bypassed the oil feeds around the studs and fed oil to the head direct like the GSX1100 kits? Those damn oil feeds can be hard to seal..

 

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On 5/2/2020 at 3:51 AM, kiwi said:

Twin plug is the way i am hopefully going too as already got 2 off 4 lead coils and ignition box (y) 

Excellent choice! Runs cooler and spark can be retarded big time..

IMG_2693.JPG

IMG_2691.JPG

DSC_0053.JPG

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5 hours ago, smithy09 said:

Excellent choice! Runs cooler and spark can be retarded big time..

Not a equation i had considered mine was purely to guarantee spark happens.

Why in this picture left plug looks like it has No ground electrode  is there a reason ?

868548603_TwinSparkBottom.JPG.bc638358b7078f920147d8adbfce03e3.jpg

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The main reason Pops fitted twin plugs was to reduce flame travel.

When the spark goes bang, the flame has to travel from one side of the chamber to the other. This takes time, and when you go high compression, you find you have to advance ignition big time to get the bang to happen at the right time. With my first gen motors we actually had to slot the Dyna 2000 back plate to get enough advance. The hp on the dyno just kept going up every time we advanced it. (I think we gained around 10-15 hp just on timing..)

The problem is that because ignition takes a long time, the engine runs hot, and you don't get an efficient burn. Changing to 2 plug  changed everything and we retarded the timing big time. It also helped get rid of some light-switch type hp issues around 4500rpm which was a real pain when the power suddenly came on mid corner!! 

So I'm a big fan of twin plug set ups! Of course in the 16 valve engine they solved all this by putting the plug in the centre and swirling the mixture to get a better mix and better bang from factory!

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2 hours ago, kiwi said:

Not a equation i had considered mine was purely to guarantee spark happens.

Why in this picture left plug looks like it has No ground electrode  is there a reason ?

868548603_TwinSparkBottom.JPG.bc638358b7078f920147d8adbfce03e3.jpg

Hahaha, yes, easier to measure where to start drilling for the other sparkplug.

 

I measured from the edge of the "dome" in the head, that's why I cut the electrode off.

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8 hours ago, smithy09 said:

Excellent choice! Runs cooler and spark can be retarded big time..

IMG_2693.JPG

IMG_2691.JPG

DSC_0053.JPG

That's a nice head!

 

I've got another head that's twin spark, it's also gas flowed (by Brian Johnson if I'm correct, no clue if that means anything to someone), it's piece of art, but the w#anker who sold it to me said it had the bearing caps still with it, it had bearing caps indeed, but when I put the cams in and thighten the caps the cams wouldn't turn anymore..

I honed out the bores a bit so the cams can turn, but I don't trust it anymore, that's why I made my old head twin spark. 

I did use the flowed head for a while, I didn't have any problems with it, but I still don't trust it.

If you have too much clearence on bearings you can get exesive wear..

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28 minutes ago, smithy09 said:

The main reason Pops fitted twin plugs was to reduce flame travel.

When the spark goes bang, the flame has to travel from one side of the chamber to the other. This takes time, and when you go high compression, you find you have to advance ignition big time to get the bang to happen at the right time. With my first gen motors we actually had to slot the Dyna 2000 back plate to get enough advance. The hp on the dyno just kept going up every time we advanced it. (I think we gained around 10-15 hp just on timing..)

The problem is that because ignition takes a long time, the engine runs hot, and you don't get an efficient burn. Changing to 2 plug  changed everything and we retarded the timing big time. It also helped get rid of some light-switch type hp issues around 4500rpm which was a real pain when the power suddenly came on mid corner!! 

So I'm a big fan of twin plug set ups! Of course in the 16 valve engine they solved all this by putting the plug in the centre and swirling the mixture to get a better mix and better bang from factory!

As far as I know it reduces the chance of detonation.

My bike runs a bit smoother, it's not a great deal, but you notice the difference.

 

Some say you can/have to retard the ignition with twin spark... Don't!

I also put a turbo one mine, so I retarded the ignition because of the twin spark and because of turbo, I added it; 3 + 4 degrees... Lost a lot of power!!

No I have the ignition at the stock setting with 7 psi, and it runs very nice, idles ok, I can ride it easily to about 2000 rpm, picks up very well, and no detonation. (although 7 psi isn't much)

 

I think I have now on 7 psi boost as much power as what I had before on 17psi with a retarded ignition, but the bike runs way better.

 

The right ignition timing is very important, stay as close to stock as possible..

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9 hours ago, Reinhoud said:

I've got another head that's twin spark, it's also gas flowed (by Brian Johnson if I'm correct, no clue if that means anything to someone), it's piece of art, but the w#anker who sold it to me said it had the bearing caps still with it, it had bearing caps indeed, but when I put the cams in and thighten the caps the cams wouldn't turn anymore..

I honed out the bores a bit so the cams can turn, but I don't trust it anymore, that's why I made my old head twin spark. 

I did use the flowed head for a while, I didn't have any problems with it, but I still don't trust it.

If you have too much clearence on bearings you can get exesive wear..

Yeah - any work by BJ means something to us oldies LOL!  His website used to have details how to bronze skull a head for TF racing - it was a work of art considering it was done in the shed at the bottom of his garden!

I think there was an old skool fix for damaged cam bearings - you line bore them oversize to take shell bearings from a Kawa - never seen it done, just heard about it.

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14 hours ago, Reinhoud said:

As far as I know it reduces the chance of detonation.

My bike runs a bit smoother, it's not a great deal, but you notice the difference.

 

Some say you can/have to retard the ignition with twin spark... Don't!

I also put a turbo one mine, so I retarded the ignition because of the twin spark and because of turbo, I added it; 3 + 4 degrees... Lost a lot of power!!

No I have the ignition at the stock setting with 7 psi, and it runs very nice, idles ok, I can ride it easily to about 2000 rpm, picks up very well, and no detonation. (although 7 psi isn't much)

 

I think I have now on 7 psi boost as much power as what I had before on 17psi with a retarded ignition, but the bike runs way better.

 

The right ignition timing is very important, stay as close to stock as possible..

When I say we retarded the ignition, this was compared to the massive advance we had pre twin plug head. You cannot say "Don't" to apply across the board. All my timing mods were done on the dyno with back to back runs. Advancing the timing with a single plug head and around 11.5:1 compression made a massive difference. We gained 10-15 hp, might have even been more. However the heat generated must have been substantial and like you say, the chance of detonation is also there. When we went to twin plug, the timing was dialed right back, probably to around standard timing, yes. I have no experience with turbo'd engines but I guess it is just like having a very high compression engine, and the twin plug set up will help a lot.

 

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Posted (edited)
13 hours ago, Gixer1460 said:

Yeah - any work by BJ means something to us oldies LOL!  His website used to have details how to bronze skull a head for TF racing - it was a work of art considering it was done in the shed at the bottom of his garden!

I think there was an old skool fix for damaged cam bearings - you line bore them oversize to take shell bearings from a Kawa - never seen it done, just heard about it.

I can't find anyone who can do the line boring, the small size is the biggest challenge as far as I know.

 

I can't get good photo's of it, or else I would post it.

Edited by Reinhoud
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