Anyone running a 1238 GS1000 on the street?

[Anonymous]

Hap, I have to agree....These are part of the revised European Pro-stock rules taken from http://www.dragbikes.com/.



Date: 11th December 2003
Headline: UEM Rule changes


Gossip:
The 2004 UEM rulebook has now been published. Important changes to the rules include Pro Stock Bike weight breaks, the relinquishing of the requirement for an annual medical examination until a rider reaches the age of 55, an increase in the prize fund and a standardisation of the ticket allocation to entrants.

The full rule book will be posted on our UEM Championship tomorrow:-

RR09 .1.1 Weight Limits

Minimum weights of bike and rider equipped with:

2-valve DOHC 265 kg max. 1510 cc

4 or 5 valve 265 kg max. 1300 cc

2-valve DOHC 270 kg max. 1600 cc

4 or 5 valve 280 kg max. 1600 cc

2, 4 or 5 valve 285 kg max. 1650 cc

2 cylinder / pushrod 250 kg max. 3000 cc

2 cylinder 220 kg max. 2000 cc

2-stroke 220 kg/n?o allowed max. 1000 cc

For combinations running fuel injection, an additional 10kg must be added to the weight. Use of UEM approve after market cylinder head, add 10kg to the weight.

To get somewhere nearer to the original topic, its been suggested that Rick Gero ran 80mm pistons in a stock block(with big liners) in his GS1000 pro-stocker way back in the late '70's/early '80's. I guess the only way to find out is to try it, although 76mm(1176cc) or 78mm(1238cc) used to be much more common. Anyone forsee any problems in using Wiseco or MTC Kawa Z/GPz pistons?

Paul,
didn't Alan Jefferies race a Kawasaki(?) Funny Bike back in the '80's. What's he doing these days?

Finally, anybody have any experience of 8-plug heads???....

[Paul]

To get somewhere nearer to the original topic, its been suggested that Rick Gero ran 80mm pistons in a stock block(with big liners) in his GS1000 pro-stocker way back in the late '70's/early '80's. I guess the only way to find out is to try it, although 76mm(1176cc) or 78mm(1238cc) used to be much more common. Anyone forsee any problems in using Wiseco or MTC Kawa Z/GPz pistons?

Paul,
didn't Alan Jefferies race a Kawasaki(?) Funny Bike back in the '80's. What's he doing these days?

Finally, anybody have any experience of 8-plug heads???....

One reason that a lot of people used 78mm(1238cc) pistons was that they were the largest that Wiseco made for the GS1000! I've just sold a GS1000 block that was fitted with 78mm GPZ pistons, so that is a good substitute for Suzuki pistons. Running bigger pistons could (would?) cause overheating problems, but if you have a large enough budget to go racing it isn't so much of a problem!

Yes, that's the same Alan Jefferies - last I heard he was working on his own building engines for road guys, that was a couple of years back.

8 plug heads - talk to Craig Smith in New Zealand.

You must be in UK, Yoshiman, whereabouts are you?

[Anonymous]

Paul,

Yes I'm in the UK, Yorkshire to be more precise. Currently in the process of making a few changes to my recently acquired GS1238 Superstreet bike. I'll be running at the Northern events (Straightliners) in 2004, and maybe at the Pod if a.)budget allows, and b.)I can run some decent times. I'm working to a fairly tight budget and don't want to get into that downward spiral of throwing big amounts of cash away in the quest for losing an extra tenth on the quarter.....
I'd like to build a spare motor over the winter, so if you've got any more 1238 blocks/pistons,etc. let me know!?!

[Paul]

Paul,

I'm working to a fairly tight budget and don't want to get into that downward spiral of throwing big amounts of cash away in the quest for losing an extra tenth on the quarter.....

I thought that was what drag-racing was all about - and when you've got no money left you retire because you've lost interest :roll: :roll: :roll:
What sort of times is this Superstreet running?
What history has it got?

I'd like to build a spare motor over the winter, so if you've got any more 1238 blocks/pistons,etc. let me know!?!

Sorry, I sold my spare to a guy in Dorset. I do have quite a lot of spare drag race only stuff.

[Anonymous]

Yoshiman I have sent you a PM.

[Anonymous]

brit7.11 and Paul: You've got email/pm

[massakins]

A few years ago in the stateside Pro Stock classes the rules were changed to handicap the dominant 4 valve Suzuki racers, thus leveling the playing field for the 2 valve Kawasaki racers. The handicap was primarily the displacement limits previously listed. This resulted in many of the Suzuki racers retrofitting the '80 and later 2v Suzuki heads to their 4v engines (requires relocating 2 (?) cylinder studs and external oiling). This allowed the racers to keep their existing clutches, transmissions and development investment intact. Note that the GPz1100 motors of '82 and later used 18mm wrist pins, like the Suzukis, so pistons were plentiful; for reference the KZ900-1000 motors were 17mm, GS750 2v motors were 16mm and GS1150 motors were 20mm. Later the Pro Stock rules were again changed to allow aftermarket cylinder heads which reduced the usage of the OEM Suzuki version. If memory serves, Russ Olmstead from Texas was the last one to run a complete GS1000 2v based motor on the national Pro Stock tour.

[Anonymous]

Interesting info. on the development of the Pro Stock rules. Thanks Massakins.
The Vortex heads that the Pro Stock guys use now are works of art, and should flow serious amounts of air through their 47/36 valves!

I guess anything can be made to fit anything given enough time, skill and money, but as a GS1000 head can with work be fitted on a 4V bottom end, and a GSXR head can also be fitted on a 4V bottom end, then I'm wondering if a GSXR head will fit on a GS1000 bottom(sounds like it'd need some welding and some new stud holes...!?!) That would really confuse people

[Hap Call]

I guess anything can be made to fit anything given enough time, skill and money, but as a GS1000 head can with work be fitted on a 4V bottom end, and a GSXR head can also be fitted on a 4V bottom end, then I'm wondering if a GSXR head will fit on a GS1000 bottom(sounds like it'd need some welding and some new stud holes...!?!) That would really confuse people

You mean like this?



More info at:

http://www.bertaut.com/gssuzuki.html

Hap

[massakins]

One impediment to putting the high horsepower potential top ends onto the GS1000 2v lower ends is the availability (i.e. lack of) strong transmission components. Cranks and clutches can be strengthened but transmissions are rare. Plus the GS1100 4v motors will almost fall into a GS1000 2v chassis and bolt in place. Kind of suspect thats the way to go if you need more than 250hp or so. My 2 cents. Hap, how you doing these days? Hope all is well.

[Hap Call]

Doing well Pat, how about yourself? Starting to gather parts for a 1261cc spare engine. I have the cases, crank, transmission, and clutch basket so far. About to do a topend rebuild on the bike within the next month or so...

Say hello to your family for me!

Hap