Topic: Suzuki GS based dragbike project.

[grcamna2]

Frank,when this bike is complete,how many seconds in the 1/4 have you been designing into it to run ?    9 or less ?

[Leino]

Frank,when this bike is complete,how many seconds in the 1/4 have you been designing into it to run ?    9 or less ?

4.60 @ 1/8

[Leino]

That translates to low 7's @ 1/4 if my memory and math are correct 

[dragracer]

Frank,when this bike is complete,how many seconds in the 1/4 have you been designing into it to run ?    9 or less ?

Legno got it right.  Mid to low 7 seconds in the 1/4 mile per most conversion calculators. I'm not that interested in going low 7's due to the speed associated with that ET. The bike is being primarily built for racing in the 1/8 mile 4.60 index class. I may race it initially in top sportsman which is a 1/4 me class but it'll have a very mild tune up with a target ET of 7.60-7.70s.

[dragracer]

It's coming along now.

[Jerry Rxman Griffin aka MuthaF'er]

What will you be riding next month?

[grcamna2]

Frank,when this bike is complete,how many seconds in the 1/4 have you been designing into it to run ?    9 or less ?

Legno got it right.  Mid to low 7 seconds in the 1/4 mile per most conversion calculators. I'm not that interested in going low 7's due to the speed associated with that ET. The bike is being primarily built for racing in the 1/8 mile 4.60 index class. I may race it initially in top sportsman which is a 1/4 me class but it'll have a very mild tune up with a target ET of 7.60-7.70s.

Oh Yeah ! ! 

[dragracer]

What will you be riding next month?

If we come, I'll be on old trusty in street ET,  on my small tire Kaw in 9.50 index and may run top gas on my car tire bike.

[Don R]

 Those 1/8 and 1/4 mile numbers compare to what our 950+ hp dragster runs on a good day. The conversion sounds legit to me.
 I agree if you are serious about racing a bike, a Suzuki is the way to go. Anything else is blazing your own trail, which is fine but harder and more expensive.

[dragracer]

Those 1/8 and 1/4 mile numbers compare to what our 950+ hp dragster runs on a good day. The conversion sounds legit to me.
 I agree if you are serious about racing a bike, a Suzuki is the way to go. Anything else is blazing your own trail, which is fine but harder and more expensive.

Don, Suzuki's do make more horsepower versus a Kaw when directly comparing cc's. It come down to the head. 4 valve per cylinder Zuks or 2 valves per cylinder Kaws. As far as scales of economy, Zuks are  more expensive to build versus a Kaw due to factory engine design shortcomings that must be overcome when doing a hipo build. Moreover,  Zuks cases are getting harder to find and the prices are exorbitant these days. I'm
fortunate to have collected GS engines and cases over the years so stock replacement pieces won't be a problem.  The modified hipo stuff is available for a price.  When considering a platform for a 4.60 index bike, it really present an advantage over building a Kaw because you'll end of adding nitrous oxide as a power adder to either platform. The Kaws hold up just as well and are equally competitive in that class. As you move quicker into the pro mod category,  Kaws are power deficient and less competitive. 

I'm hoping for the best on this project and will try to keep you guys posted more often now that the chassis is almost done and will be in my possession soon.

[Don R]

 I'm re-building a 70's period cb750 based turbo dragbike but it's really just going to be a street freak/show bike and an exercise in making old stuff work. 

[dragracer]

Talked to the chassis shop guy today. He's about done. Just needs to mount the front fairing now and then weld up the foot peg mounts when I get there. We want to be certain I'm comfortable on the bike.  Looking now like I'll be making a trip down to Florida mid-week for the pickup. If I had to do this again,  I'd probably just build a Kaw motor and drop it in since the mounts were already there for the brand. I would have saved myself a few grand or more. Nevertheless,  I feel I'll be satisfied with the Suzuki platform because it'll make more raw horsepower and I'll only need a small shot of nitrous oxide to run the 4.60 index. Should be a way to save parts in the Ling run.  I'll keep you all updated next week when I get an opportunity. 


On another note, I finally got around to taking the new 750 build back to the track today for some testing. I had swapped out the throttle for a quick turn tube from an R1. Because my WOT switch was modified to activate against the smaller throttle tube and it was no longer usable, I had to rig up another setup on the shaft of the carbs with a 3 way microswitch instead. I also increased the ignition kill time for the airshifer because it wouldn't shift properly the last time it was out. My fist pass netted a 10.40ET @123mph. The bike didn't react quick enough at the launch eventhough it was a respectable 1.44 sixty foot time. The problem is the bike has produced a 1.29 sixty foot so I knew something has gone backwards.  On a positive note, the bike shifted perfectly but with a tad longer kill time between shifts than i prefer. Back in the pits i was told by a fellow racer that the bike simpky didn't reaction when i dumped the clutch. Dang it. I decided to decrease the kill time between shifts on the the next pass to see if it would still work okay. I tried to be more aware of how I was releasing the clutch to be certain I wasn't dragging the lever. On that pass I had a slower sixty foot, a 1.51 and the bike ran a 10.45@122.92mph. Sheesh. I made my f3rd and final pass and it was no improvement,  a 1.50 sixty foot and it only ran a 10.54@119mph. I fanned the shift button twice for some reason and caused a short shift. I noticed back in the pit area that the clutch lever had abnormal free play. Obviously I had some clutch problems that need to be addressed because the bike no longer reacts as quick as it did and the mph is down indicating clutch slippage. I'll pull the pack out next week and determine what I've got going on. 🤪  I'm definitely not to happy right now with the ET or mph but the engine sounded good and I have no known oil leaks. I can deal with the rest. Stay tuned on all fronts. 🤣

[RAFster122s]

Exciting times…
New chassis should be fun for the Suzuki build. Well, it was a test you were running on the 750 and nothing broke, so that is a plus I would say…
Some diagnostic on the clutch and few adjustments and hopefully the next outing will bring a smile to your face. It is getting down the track pretty quick, so that is encouraging.

[dragracer]

Exciting times…
New chassis should be fun for the Suzuki build. Well, it was a test you were running on the 750 and nothing broke, so that is a plus I would say…
Some diagnostic on the clutch and few adjustments and hopefully the next outing will bring a smile to your face. It is getting down the track pretty quick, so that is encouraging.

It was a good day to be playing at the dragstrip. Weather was perfect, not many folk testing and the track conditions were excellent.

I shouldn't feel bad about the performance of the bike. I always remove clutches  for inspection after a few passes on a new build but neglected to take these out since they were installed. In the back of my mind, i kind of felt the current setup may not absorb the power for long.  The increase in the 60' numbers is an indicator the clutch is going away. I just have to sit down and decide the best corrective action to restore and maintain consistent launches from this point forward.

[grcamna2]

Talked to the chassis shop guy today. He's about done. Just needs to mount the front fairing now and then weld up the foot peg mounts when I get there. We want to be certain I'm comfortable on the bike.  Looking now like I'll be making a trip down to Florida mid-week for the pickup. If I had to do this again,  I'd probably just build a Kaw motor and drop it in since the mounts were already there for the brand. I would have saved myself a few grand or more. Nevertheless,  I feel I'll be satisfied with the Suzuki platform because it'll make more raw horsepower and I'll only need a small shot of nitrous oxide to run the 4.60 index. Should be a way to save parts in the Ling run.  I'll keep you all updated next week when I get an opportunity. 


On another note, I finally got around to taking the new 750 build back to the track today for some testing. I had swapped out the throttle for a quick turn tube from an R1. Because my WOT switch was modified to activate against the smaller throttle tube and it was no longer usable, I had to rig up another setup on the shaft of the carbs with a 3 way microswitch instead. I also increased the ignition kill time for the airshifer because it wouldn't shift properly the last time it was out. My fist pass netted a 10.40ET @123mph. The bike didn't react quick enough at the launch eventhough it was a respectable 1.44 sixty foot time. The problem is the bike has produced a 1.29 sixty foot so I knew something has gone backwards.  On a positive note, the bike shifted perfectly but with a tad longer kill time between shifts than i prefer. Back in the pits i was told by a fellow racer that the bike simpky didn't reaction when i dumped the clutch. Dang it. I decided to decrease the kill time between shifts on the the next pass to see if it would still work okay. I tried to be more aware of how I was releasing the clutch to be certain I wasn't dragging the lever. On that pass I had a slower sixty foot, a 1.51 and the bike ran a 10.45@122.92mph. Sheesh. I made my f3rd and final pass and it was no improvement,  a 1.50 sixty foot and it only ran a 10.54@119mph. I fanned the shift button twice for some reason and caused a short shift. I noticed back in the pit area that the clutch lever had abnormal free play. Obviously I had some clutch problems that need to be addressed because the bike no longer reacts as quick as it did and the mph is down indicating clutch slippage. I'll pull the pack out next week and determine what I've got going on. 🤪  I'm definitely not to happy right now with the ET or mph but the engine sounded good and I have no known oil leaks. I can deal with the rest. Stay tuned on all fronts. 🤣

How's your GS1100E engine ? 

[dragracer]

Talked to the chassis shop guy today. He's about done. Just needs to mount the front fairing now and then weld up the foot peg mounts when I get there. We want to be certain I'm comfortable on the bike.  Looking now like I'll be making a trip down to Florida mid-week for the pickup. If I had to do this again,  I'd probably just build a Kaw motor and drop it in since the mounts were already there for the brand. I would have saved myself a few grand or more. Nevertheless,  I feel I'll be satisfied with the Suzuki platform because it'll make more raw horsepower and I'll only need a small shot of nitrous oxide to run the 4.60 index. Should be a way to save parts in the Ling run.  I'll keep you all updated next week when I get an opportunity. 


On another note, I finally got around to taking the new 750 build back to the track today for some testing. I had swapped out the throttle for a quick turn tube from an R1. Because my WOT switch was modified to activate against the smaller throttle tube and it was no longer usable, I had to rig up another setup on the shaft of the carbs with a 3 way microswitch instead. I also increased the ignition kill time for the airshifer because it wouldn't shift properly the last time it was out. My fist pass netted a 10.40ET @123mph. The bike didn't react quick enough at the launch eventhough it was a respectable 1.44 sixty foot time. The problem is the bike has produced a 1.29 sixty foot so I knew something has gone backwards.  On a positive note, the bike shifted perfectly but with a tad longer kill time between shifts than i prefer. Back in the pits i was told by a fellow racer that the bike simpky didn't reaction when i dumped the clutch. Dang it. I decided to decrease the kill time between shifts on the the next pass to see if it would still work okay. I tried to be more aware of how I was releasing the clutch to be certain I wasn't dragging the lever. On that pass I had a slower sixty foot, a 1.51 and the bike ran a 10.45@122.92mph. Sheesh. I made my f3rd and final pass and it was no improvement,  a 1.50 sixty foot and it only ran a 10.54@119mph. I fanned the shift button twice for some reason and caused a short shift. I noticed back in the pit area that the clutch lever had abnormal free play. Obviously I had some clutch problems that need to be addressed because the bike no longer reacts as quick as it did and the mph is down indicating clutch slippage. I'll pull the pack out next week and determine what I've got going on. 🤪  I'm definitely not to happy right now with the ET or mph but the engine sounded good and I have no known oil leaks. I can deal with the rest. Stay tuned on all fronts. 🤣

How's your GS1100E engine ? 

Have not started working on the engine yet but will do so once I get the chassis in my shop.

[dragracer]

I did put the head on the stands to check it over since this picture was taken. Over than that, no true work progress on the powerplant.

[grcamna2]

I did put the head on the stands to check it over since this picture was taken. Over than that, no true work progress on the powerplant.

How radical is the porting on it ?

[MauiK3]

That head looks a lot like a Kawasaki head.

[dragracer]

I did put the head on the stands to check it over since this picture was taken. Over than that, no true work progress on the powerplant.

How radical is the porting on it

I did put the head on the stands to check it over since this picture was taken. Over than that, no true work progress on the powerplant.

How radical is the porting on it ?

Extensive porting. As you can see, stock carb intake boots,are no longer used. It has Dayco hose large enough to accommodate 44mm Lectron carbs. Oversized titanium intake and exhaust valves on big seats.

[dragracer]

That head looks a lot like a Kawasaki head.

No. It's a 16 valve GS1100 head. Note the rocker arms. Kaws use under bucket shims for big cams.

[dragracer]

It's ready for pickip.  I'm on I-95 SOUTH  right now headed for Florida.  Burn and turn.

[RAFster122s]

Baby has got back...

[grcamna2]

YEAH !! 

[Leino]

Well that looks like a serious racebike