Going Big cc

[Guest]

I haven?t posted in a while. I been busy working, building, and racing
I have decided that I want to run 4.60 class the quickest of all the index classes. I already have the chassis so I am going big motor 1640cc. The motor build is a GS 1100 motor with a 31/26 valve GSXR 1100 Nicely ported head, 425/390 cams, sitting on some 87mm 15 to 1 pistons, 68mm stroked crank with Falcon rods 750 gear, a 1,2,3, auto trans with billet shafts and 2nd gear, and a slider clutch, all breathing through some 44mm Lectrons. It will still need to sniff a little spray to run 4.60 and Top Gas on motor.
With this build and a couple other changes to two of my other bikes I will have every index class covered. Everything from 4.60 to Street Et. Just call me the Index Kitt

 

[Nessism]

Sounds like fun! And expensive! None of my business of course but how much $ to build an engine like you mention?

 

[steve murdoch]

4.60 Class comes with speeds in the 150mph range.....wow!
Stet, it would be great if you could give us some periodic reports on your competitions this summer.
In this video of 4.60 qualifying it shows wide variety of machines.
https://www.youtube.com/watch?v=bIyfyIpey1M

 

[Guest]

Sounds like fun! And expensive! None of my business of course but how much $ to build an engine like you mention?

I am getting alot of help from some great people. Jay at MRE and Mike at M&J Preformance. But I could buy a ready to go Motor for 8G?s

 

[glib]

Must be an exhilarating launch!

 

[Guest]

Must be an exhilarating launch!

It?s the only bike I have ever raced and still had a big grin on my face after losing the round.

 

[blowerbike]

IMO the 750 ratio gears are only for a live clutch because of how much it slows down the clutch basket.
again..just my opinion.

 

[rapidray]

I agree with Terry, the 750 ratio clutch gear will make tuning a slider a lot more interesting. It CAN be done but isn't easy & very few use that ratio on a slider.
Ray.

 

[cbxchris]

I quit mid 90's. 4.60 was a good bike at that time.

I went a different route. I used turbo with a touch of gas. I kept the gas on a button. 3 speed OE. Jay often fixed my junk. It took 3 trannys to keep 2 working. Other than tranny's that was a very reliable set up. At the time top gas was 8.20. We just had a hard time running that slow. Often we attended outlaw races that had extremely fast indexes but they were still index. Rockingham Dragway often had a 7.60 then moved to 7.40 later which weeded at lot of people out that couldn't run the number. I was one of the first to go two step slider with no magneto on turbo applications. People said it would never work. We won so much in the old southern cycle racing series they basically said....don't come back.

You're going a way that I thought of many times. If I had stayed in it I probably would have. What your wheelbase? I used a Kosman sit up 1150 style. I want to say we ended up at 74 inches with a 11 inch tire. Its been a while. We payed around with several set ups.

We never used 750 gears nor used external oil lines. I milled the heads/head gaskets to accept GSXR oil galley o rings.... I usually got a piston or two occasionally in 1/4 mile runs with the 7:40 index. I finally put sleeves in and started at 1325 then ended at 1425...then again of course had to resleeve. You could see the 100cc's in our 60 ft's...but other than that for us the 1325 ran as good.

Miss the days...
Don't miss the nights working on them
Don't miss spending the money..
Love the memories.....

 

[Guest]

cbxchris
The wheel base is 69” it is 42” from crank to rear axle. Rear tire is a 28/10.5/15. It is an older Paul Gast chassis. Very similar to a Kosman chassis.

Ray
we are already are using sliders with the 750 ratio. It just takes more weight. Alot more between 20 to 28 grams.
I am running 21 grams on my GSXR 1100 pro et bike.

 

[Guest]

Update!
got a 1150 head. I was going to port my own head for this build but I found a GS 1150 head already ported with big titanium valves 33/27 to go with my 1640cc big motor. My little short bus is gonna haul a$$!!

 

[Guest]

Peek inside

 

[storm 64]

That's some serious hardware there.
Are you going to Valdosta in November? I'm going to try to make that race. All the top guys will be there

 

[Guest]

Hey Steve... Jealous of your stable. Good luck with the 4.60 index. Just been staying near home in Illinois. Maybe one of these days I will get to Bradenten.
Will watch progress when I can.
Curt
Email is easier. hermann1us@yahoo.com

 

[Guest]

My names not Steve LOL! It is J.D.
I have a few but it takes up alot of my time. The 4.60 build will be taking longer than I anticipated due to having a pack of gremlins jumping on my Pro Et bike. So I have to completely re wire the Pro Et bike and install some new goodies on it. I got a new delay box and LED dial-in board and a throttle stop for it.
I did pick up some 48mm Lectrons for the 4.60 bike so I can test the bike before I go to F.I. It still needs some/alot of $$$ parts. It is costing more than I thought. I should have, could have just bought a bike already built for the 4.60 index. But it would be someone else?s build.
On a happy note I got runner up at the Snowbirds Nationals and the man I lost against I built and tune his motors.