Need the BIG bore guru's

[ozman]

wanting to built a 2 valve around 160hp road race engine
1200 to 1300 cc
i have numerous GS1000 motors just bought a GS1100GK motor for parts eg head D port, barrels, crank if needed
what are my options remembering it need to be somewhat reliable not pulled down after each race
all contributions welcome
oz

 

[rapidray]

Set it up with NO more than 12.5 to 1 compression, no bigger than .470 lift, try to get an 1100 block & 3mm over pistons for it, & send the head to ME!!! LOL!! I know you should be able to find someone in your homeland to do the head. I would look for a CV carbed, large port head to start with & go 1mm bigger valves on both intakes & exhaust valves. Around 100 cfm in airflow & the above parts, with 36mm RS Mikunis should get you close to your power goal. Keep in mind, you also need a good ignition system! You also need to have the crank & clutch hub welded & strengthened. The above engine will be reliable, make good power, & not be hard on parts or need a lot of maintenance. Ray.

 

[ozman]

thx ray
just few other points for you to contemplate
can only use keihin CR carbs or similar style no flat slides
i have the 1100GK block and head havnt checked but i assume GS1100 block has more meat around sleeves than the 1000 block ?
value in twin plugging head or not ? (very old argument this one)
crank from GS1100 longer stroke than GS1000 ? ive seen it mentioned about changing rods and using in GS1000 crankcases true or not ?
looking at adapting slipper clutch into motor its common here on post classic racers
ignition sorted using a self energizing setup
oz

 

[GregT]

What he said plus if you're building it for Post Classic roadracing you'll be looking for Keihin CR's around 35mm - and jetting for Methanol...

I haven't got the link but Smithy on oldskoolsuzuki has been there. written it up, run out of money etc etc....

 

[ozman]

agreed about the CR's and methanol greg just canvasing all the idea's to see if theres something we missed in options or something new someone has found
my engine builder was muttering about 1294cc its way outside anything ive built, kinda treading in unexplored territory for me
oz

 

[blowerbike]

hi,
i received your P/M.
i'm not sure of which parts from what engines to use but..
John Pearson has done this and could pass on the needed info.
he is a crank builder so i assume this is how he found the mix/max formula for the 1100 shafty crank to fit in GS1000 chain drive cases.
i know the shafty primary gear is on the opposite throw and has to be swapped out for i believe a 16v. 1100 throw to get the primary gear in the correct location for the 8v. chain drive engine cases.
his number is:
937-839-9723

 

[BadBillyB]

Why is it that every person who decides to build a bad ass GS1000 2V motor either lives in Australia or Canada....I have all the goodies here in sunny Florida and want to let them go for cheap. I quit drag racing in 1991 and cant stand to see all these nice parts collect dust. I have....
APE Big block (probably only one of ten ever built)
Chromoly case studs
Chromoly cylinder studs
Big port head, fully ported for high velocity, with
40mm titanium intake valves (Vance & Hines Racing)
33mm titanium exhaust valves, also VHR
Oversize seats courtesy of Star Racing (serdi valve job)
Titanium retainers
Shim under buckets (MTC)
Forged (not billet) MTC clutch basket w/straight cut gear (no wear at all)
w/all necessary parts to fit GS 2V motor
1-2-3 Automatic overriding transmission prepped by MRE

ETC........Would like to see one person take it all....The cylinder head alone is worth over 3 thousand dollars.... Just to stay on topic, In my opinion, the best set up for the crankshaft would be to use the GS1000 crank (64.8 mm) with the longer GS1100 rods......The reason I quit racing was breaking 2 crankshafts back to back. Both were 1100 cranks prepped by Falicon at the tune of $1600....Something about the bearing spacing on cylinder #2 caused the crank throw to come apart......This was a 1260cc motor N/A that ran 8.30's in the 1/4 mile.....MPH's were 155 to 156......Never broke anything before (except for a stock clutch basket) putting the GS1100 crankshaft in it....Hundreds of passes.....The GK motor (crank & block) I really dont have experience with, I only used the cylinder head ..........Billy

 

[kochic]

Why is it that every person who decides to build a bad ass GS1000 2V motor either lives in Australia or Canada....Badbillyb.


The voices made me do it:twistedevil::twistedevil::twistedevil::twistede vil::twistedevil:.
I have no passport yet, but can have one and drove to the sunshine state this spring....:-k:-k
PM me.
marc

 

[ozman]

pm sent to billy

 

[blowerbike]

damn billy...1991?
did you still go to and follow IDBA/dragbike!/prostar?
you do have a hoard of good 8 valve shlt...i think you may be putting your stuff in a container and shipping it to OZ.

 

[dardoonk]

Not everyone is outside the US.

 

[blowerbike]

Not everyone is outside the US.

i thought everybody had talked to in to doing a 16 valver

 

[dardoonk]

Nah, seems like that's the common path... I want to build a big 8V because nobody does it anymore. I'm not out to build a race motor & making it streetable will present a challenge, but I'll have fun with it.
Plus, I've already got a set of 79mm JE pistons, rings & a sleeved block with liners sturdy enough to last.. I need cams, gaskets, a beefier clutch & whatever I decide to do on the head.

 

[BadBillyB]

damn billy...1991?
did you still go to and follow IDBA/dragbike!/prostar?

I wish.....I have had a Pro license with all 3 organizations in my life time and also NHRA pro license. Actually ran and qualified in NHRA Pro Stock Bike back in 1986 at Gainesville Florida.....Byron Hines was walking circles around my GS1000 "L" model in the staging lanes trying to figure out how and the hell a street bike was qualified to run in the program....Made my day.....All 3 organizations are now gone and the only close by races are in Georgia (Semdra) and south Florida (bracket racing)....Even my local 1/8 mile trackclosed down years ago (Jax Raceway).....I still love it though and follow the action on Dragbike.com.........Billy

 

[sharpy]

Pm me again. where i work part time he is the idea man for T-rex. and if u want to by JE pistons and stuff mite get u a good deal. never know till u ask

 

[trippivot]

great engines are created by very few people.

great engines are created by very few people.

Why is it that every person who decides to build a bad ass GS1000 2V motor either lives in Australia or Canada....I have all the goodies here in sunny Florida and want to let them go for cheap. I quit drag racing in 1991 and cant stand to see all these nice parts collect dust. I have....
APE Big block (probably only one of ten ever built)
Chromoly case studs
Chromoly cylinder studs
Big port head, fully ported for high velocity, with
40mm titanium intake valves (Vance & Hines Racing)
33mm titanium exhaust valves, also VHR
Oversize seats courtesy of Star Racing (serdi valve job)
Titanium retainers
Shim under buckets (MTC)
Forged (not billet) MTC clutch basket w/straight cut gear (no wear at all)
w/all necessary parts to fit GS 2V motor
1-2-3 Automatic overriding transmission prepped by MRE

ETC........Would like to see one person take it all....The cylinder head alone is worth over 3 thousand dollars.... Just to stay on topic, In my opinion, the best set up for the crankshaft would be to use the GS1000 crank (64.8 mm) with the longer GS1100 rods......The reason I quit racing was breaking 2 crankshafts back to back. Both were 1100 cranks prepped by Falicon at the tune of $1600....Something about the bearing spacing on cylinder #2 caused the crank throw to come apart......This was a 1260cc motor N/A that ran 8.30's in the 1/4 mile.....MPH's were 155 to 156......Never broke anything before (except for a stock clutch basket) putting the GS1100 crankshaft in it....Hundreds of passes.....The GK motor (crank & block) I really dont have experience with, I only used the cylinder head ..........Billy

AMEN I had thousands of dollars of performance parts and all I got was pennies on the dollar for them. no more 2V 1000 for me, they are too fragile to put thousands of dollars into anymore.


After spending tens of thousands of dollars
I have a recipe for a 1105 cc engine producing 160 hp and able to live for thousands of miles...$3000 budget approx.

I also have a combination for a 1240 making 200+ hp - no nitrous , sadly under 30 full horse power minutes life span.$5000 U.S.D. budget

tried and true blueprint design specs for a GS1000 might be a good selling book, but I suspect proper instructions will not followed to the letter. 1 machinist does this, another machinist does that, the assembler does it "his way". and the engine owner gets jipped

My take on this thread is too many chefs' spoil a stew. What I mean is too many builders philosophies mix matching do not produce results, they produce scattered engines.

oil on the rear wheel at 100 mph is a little distressing.

 

[Guest]

If you wind up getting that block from Billy and building your bike, post some photos. I would love to see it.

 

[trippivot]

Start with your head.

Start with your head.

use that shaft drive cylinder head. concentrate on the head as a masterpiece more so than the actual displacement and other details first. Spend a lot of effort to get the best head, even if you go through a half dozen of them. It will be worth it.

40mm intake concentrate on a DEEP deep 60 degree cut way before you get to enlarging the first 0.500" of the aluminum just under the valve seat.

and 33mm exhaust will flow great and leave plenty of material to hold the seats in also not to crack to the plug or to the other seat

low valve lift head flow - and improvements there are so much more important than max lift flow and total flow. I'm not saying max flow is not important to achieve your goal- it is.

what I mean is if assuming everything is the same on a hypethetical engine

#1 head flows 35cfm at 0.100" and maxes out at 108cfm at 0.430".
#2 head flows 20cfm at 0.100" and maxes out at 120 at 0.430"

won't matter about displacement cam timing valve size because #1 is going to faster in most all situations except for very extended top gear top rev runs over multiple minutes W.O.T., no matter what the displacement of this hyp. eng.. (a valid exception is total vehicle weight)

if you're going from 4K rpm to 8K maybe over 10K and back over and over up and down the rev range. low lift valve / port flow is the key to unlocking massive gains from smaller engines without unnecessary stress and heat. ya know the usual trade off is friction- not on this specific topic, FREE POWER!

this simple theory is why a 16 valve engine is crazy fast compared to a 8 valve.

the 2 little valves flow a lot more just as the valves come off of their seats faster in, then faster out, equals faster piston acelleration. I don't need to tell you each one of your pistons COAST 3/4 of the time the engine is running. And a small light piston drags less than a big heavy one. Granted a big piston on a long stroke pushes harder not faster. ( torque-vs H.P battle of the ages)

yamaha went too far with Genesis 3 intakes 2 exhaust
honda and ford use the heck out of 2 intakes and 1 exh.

 

[Flyboy]

Thanks guys, this is really interesting stuff, please keep it coming, I am facinated by the knowlege.
When I am done with the 1000G rebuild, I want to tackle a build on a silly fast 8v, maybe a 1000S or 1000E, pretty pointless on a shaft I would imagine.

 

[ozman]

If you wind up getting that block from Billy and building your bike, post some photos. I would love to see it.

still waiting for contact with billy his parts interest me, ill be sure keep you posted if project goes ahead
oz