136 mph 200cc tiger cub
- Thread starter Texasstar
- Start date
It was the mid 60s PJ. And he was a smart guy. If I remember he was a good friend of Ed Iskenderian. And Ed ground his cams for him.
If you go to scta-bni.org and have a look at Bonneville records and check out the SCS (sidecar streamliner) records you'll see how many classes they hold records in. All with the same chassis.
If you go to scta-bni.org and have a look at Bonneville records and check out the SCS (sidecar streamliner) records you'll see how many classes they hold records in. All with the same chassis.
Texasstar
Can't is a four letter dirty word
Bill I wasn't doubting you for a second about the records. I just know that that generation wasn't loose lipped about their hard earned secrets. What I was referencing was the guy with the cub. We have a Cb200 and know how hard it is to squeeze HP out of this little motor. Now if we had a dual overhead cam and needle bearings we may be able to challenge the Cub record. But I figure we are gonna need to squeeze 30-40 HP to do that. I dont know if that is possible. Mr. Honda's Cr72 got there with 250 cc and a dual overhead cam...we need a LSR mentorHoofhearted said:
The main reason they were tight lipped was because so many of them, how can I put this politely, "stretched" the rules.
It's not hard to get more power out of a 200cc pushrod single but to get 30HP out of it is pushing technology just a little. You can always get more power out of a 200cc OHC twin than with a 200cc single with the right budget if you understand the design limitations of teh base motor.
I have seen 27 out of a 200 twin at the rear wheel, so I know it's possible to get more, but costs do go up exponentially.
Start with port flow and then look at where it's restricted and what the implications are. Then look at the whole valve/cam train and then at the bottom end and piston shapes and take it from there. 25HP is not out of reach.
It's not hard to get more power out of a 200cc pushrod single but to get 30HP out of it is pushing technology just a little. You can always get more power out of a 200cc OHC twin than with a 200cc single with the right budget if you understand the design limitations of teh base motor.
I have seen 27 out of a 200 twin at the rear wheel, so I know it's possible to get more, but costs do go up exponentially.
Start with port flow and then look at where it's restricted and what the implications are. Then look at the whole valve/cam train and then at the bottom end and piston shapes and take it from there. 25HP is not out of reach.
Texasstar, Teazer. We still aren't loose lipped.
Pushrod engines run in a separate class to OHC and two strokes. Not sure when that came into being but I think it was when the Jap liter multis arrived and the Harleys were getting killed. So a separate pushrod class was introduced. One of the go fast "secrets" is drag reduction. Drag is the killer in the small capacity classes. Anything you can tuck in out of the airflow will help. 136 from a Cub is probably not so much HP as aerodynamics. Have a look at the exploits of Muller and Hertz and their factory NSUs in 1956. Their records still stand to this day.
I have not doubt the rules back then were "stretched" and "interpreted". But with the SCTA at Bonneville if you are fortunate to set a record you go to impound and your engine is measured. Plus your gas (in the gas class) is tested. Even though you have to run "event gas" (ERC) the officials still test your gas after each record. A case of love many, trust few.
All the Cub records at Bonneville and El Mirage are under the"ton" so they are not impossible. It will just take a lot of effort.
Pushrod engines run in a separate class to OHC and two strokes. Not sure when that came into being but I think it was when the Jap liter multis arrived and the Harleys were getting killed. So a separate pushrod class was introduced. One of the go fast "secrets" is drag reduction. Drag is the killer in the small capacity classes. Anything you can tuck in out of the airflow will help. 136 from a Cub is probably not so much HP as aerodynamics. Have a look at the exploits of Muller and Hertz and their factory NSUs in 1956. Their records still stand to this day.
I have not doubt the rules back then were "stretched" and "interpreted". But with the SCTA at Bonneville if you are fortunate to set a record you go to impound and your engine is measured. Plus your gas (in the gas class) is tested. Even though you have to run "event gas" (ERC) the officials still test your gas after each record. A case of love many, trust few.
All the Cub records at Bonneville and El Mirage are under the"ton" so they are not impossible. It will just take a lot of effort.
crazypj
Split personality, I fake being smart
As with most things, yep, I have a little experience on Tiger Cub ;D
I quite liked it as it was a 'stretched' 150 so all the parts are tiny compared to even a C15
I very much doubt the motor would be bigger than 2mm over piston but the head would be welded and re-shaped
With some 'VERY SMART PEOPLE' getting involved it probably made max power around 9,500rpm although I very much doubt it made over 20bhp and probably less?
A lot of aerodynamics was still classified but 'junk' aircraft parts were around to look at and speculate with
Even so, sub 400mph air flow information couldn't have been super easy to find, particularly if your not even sure what your looking for
It's just impressive what can be done without massive budgets, low power, I guess it's another reason I 'play' with the 'ugly duckling' bikes and try to do more with less (I was 8yrs old in 1965 and 'devoured' everything I could find even remotely related to motorcycles and going fast )
Other kids, if they had any interest in bikes, were more concerned on the numbers on speedo or how much chrome/shiny things were
I probably shouldn't type and take Percocette
I quite liked it as it was a 'stretched' 150 so all the parts are tiny compared to even a C15
I very much doubt the motor would be bigger than 2mm over piston but the head would be welded and re-shaped
With some 'VERY SMART PEOPLE' getting involved it probably made max power around 9,500rpm although I very much doubt it made over 20bhp and probably less?
A lot of aerodynamics was still classified but 'junk' aircraft parts were around to look at and speculate with
Even so, sub 400mph air flow information couldn't have been super easy to find, particularly if your not even sure what your looking for
It's just impressive what can be done without massive budgets, low power, I guess it's another reason I 'play' with the 'ugly duckling' bikes and try to do more with less (I was 8yrs old in 1965 and 'devoured' everything I could find even remotely related to motorcycles and going fast )
Other kids, if they had any interest in bikes, were more concerned on the numbers on speedo or how much chrome/shiny things were
I probably shouldn't type and take Percocette
Texasstar
Can't is a four letter dirty word
Hey pj how is the recovery coming? We are saying a few prayers around here for you. If you get some divine inspiration about going fast while on percocette it is an answer to my prayer so I hope you are gracious enough to share itcrazypj said:As with most things, yep, I have a little experience on Tiger Cub ;D
I quite liked it as it was a 'stretched' 150 so all the parts are tiny compared to even a C15
I very much doubt the motor would be bigger than 2mm over piston but the head would be welded and re-shaped
With some 'VERY SMART PEOPLE' getting involved it probably made max power around 9,500rpm although I very much doubt it made over 20bhp and probably less?
A lot of aerodynamics was still classified but 'junk' aircraft parts were around to look at and speculate with
Even so, sub 400mph air flow information couldn't have been super easy to find, particularly if your not even sure what your looking for
It's just impressive what can be done without massive budgets, low power, I guess it's another reason I 'play' with the 'ugly duckling' bikes and try to do more with less (I was 8yrs old in 1965 and 'devoured' everything I could find even remotely related to motorcycles and going fast )
Other kids, if they had any interest in bikes, were more concerned on the numbers on speedo or how much chrome/shiny things were
I probably shouldn't type and take Percocette
We are also trying to go fast with less. Just got back from a run on my sons bike. New iridium plugs, 10-40 partial synthetic. This is the first run after our first dyno. Throttle response was even better 10.5k @ 76 mph. We lost 4 lbs by changing the battery but we had a net gain of 6lbs since I gained 10 on vacation ...6'5" 217lbs. No more gear left. Running a stock 17 front 38 back...thinking about going up 2-4 on the back. Any thoughts?
Here's an oldie but goodie. It makes you look at your bike and think. At least it did me.
http://www.youtube.com/watch?v=ftq8jTQ8ANE
Particularly the drag of an airfoil vs. a round tube. So when I built the new sidecar platform I tried to turn the support tubes into airfoils. Not the perfect shape but I figure it will help more than it hurts.. Not that it matters a damn. The SCTA are having major reluctance in approving solid wheel. They want a PE's stamp and signature.
http://www.youtube.com/watch?v=ftq8jTQ8ANE
Particularly the drag of an airfoil vs. a round tube. So when I built the new sidecar platform I tried to turn the support tubes into airfoils. Not the perfect shape but I figure it will help more than it hurts.. Not that it matters a damn. The SCTA are having major reluctance in approving solid wheel. They want a PE's stamp and signature.
Texasstar
Can't is a four letter dirty word
The Vintage motorcycle magazine told a story about Pete Dalio and Jack Wilson. Pete had a competitor move in down the street and challenge them to a race stock bike to stock bike. Well Pete was a win at all cost type of guy and had Jack Wilson rod up the stock bike overnight. Jack put in a new cam etc and when he was finished nobody could tell that the motor was touched. The Dalio Triumph won that race. I am sure those two had something to do with why the Bonneville rules are the way they are today...Hoofhearted said:
(Revision) talked to Keith Martin and he said this story was BS. Don't believe everything you read in a vintage magazine! He said the that Jack said the best feeling in the world is to beat a cheater!
Texasstar
Can't is a four letter dirty word
not yet on the clutch springs and I could feel the clutch slip before so I made an adjustment. The first pick is dyno run 1 and 2. We removed the filter off the velocity stack for the second run. Both runs re ran off the chart rich.crazypj said:
For runs 3, 4,5 we rejected from 100's to 90's. We gained 1500 rpms and 2 HP. The dyno said we were still off the chart rich.
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crazypj
Split personality, I fake being smart
What bike is it? I though you were doing a CB350?
That should show about 34bhp
If it's a 125, that's pretty good for super rich mixture, will probaby jump another 2 bhp with correct jetting
What exhaust are you using?
Too short really messes up mixture
OK, CB200, with those pipes you probably want 78~82.5 main jets
It's probably easier to get some tube that will slip over the pipes ad test different exhaust lengths, the intakes are also too short, if you take a look at some vintage Honda's you'll see they are much longer to work properly, you probably have 7"~9" from valve head, that should be good for 13,000+rpm ;D
That should show about 34bhp
If it's a 125, that's pretty good for super rich mixture, will probaby jump another 2 bhp with correct jetting
What exhaust are you using?
Too short really messes up mixture
OK, CB200, with those pipes you probably want 78~82.5 main jets
It's probably easier to get some tube that will slip over the pipes ad test different exhaust lengths, the intakes are also too short, if you take a look at some vintage Honda's you'll see they are much longer to work properly, you probably have 7"~9" from valve head, that should be good for 13,000+rpm ;D
Texasstar
Can't is a four letter dirty word
thanks for the video... It shows why Brett de Stoop is so fast. Have you seen this?Hoofhearted said:Here's an oldie but goodie. It makes you look at your bike and think. At least it did me.
http://www.youtube.com/watch?v=ftq8jTQ8ANE
Particularly the drag of an airfoil vs. a round tube. So when I built the new sidecar platform I tried to turn the support tubes into airfoils. Not the perfect shape but I figure it will help more than it hurts.. Not that it matters a damn. The SCTA are having major reluctance in approving solid wheel. They want a PE's stamp and signature.
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Texasstar
Can't is a four letter dirty word
yep cb 200crazypj said:
Stock cam, carb, valves. Racing cam chain and valve springs, cb750 velocity stack. The calculation I have to catch a pulse is 120mm for the length of the velocity stacks. My son wants to do a 2 into 1 exhaust and add a shorty. Do you mean something like this for the length of the intake? My fellow DTT'er's bike.
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What is the ID of the pipes you plan on using? Stock double skin pipes are not very large.
If you want a longer pipe, use a megaphone or 2 into 1 with larger diameter tailpipe and a decent collector - or both.
Long straight pipes are not good for gas flow or power.
Of course what you want for a street motor and what you want for a 100mph LSR run are not necessarily the same.
If you want a longer pipe, use a megaphone or 2 into 1 with larger diameter tailpipe and a decent collector - or both.
Long straight pipes are not good for gas flow or power.
Of course what you want for a street motor and what you want for a 100mph LSR run are not necessarily the same.
Texasstar
Can't is a four letter dirty word
PJ you are good! Yes our timing is advanced because we are running 93 octane. However we are running 89 next time and returning to our original timing. We advanced our timing until we had a slight increase of Rpms and then backed it down slightly. It really woke the motor up! See pix. Our intakes are the stock intakes...the have a rubber composite material inside...honda did this because of lean conditions in the 175. The purple marks lined up were our original timing.crazypj said:
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We found that extra ignition timing helped all through the powerband and run 45-47 degrees. At 50 degrees you lose power everywhere and the same at 40 degrees or less, but engines and fuels are not all the same. The timing that allows your motor to rev is probably optimal for that configuration.
Hondas seem to work best with long megaphones and the old race kit megs were too short. That one looks short, but try it. Go with a short tailpipe before the megaphone that is suitably larger than the primaries (headers).
I recognize that nice looking 68 sloper in a 64 CB160 chassis, with CB200 head, VM26 carbs and crank mounted Dyna S. It's one I built and it's still in the garage last time I checked. Headers came from a cheap swap meet 400 Bandit 4 into 1 that provided enough bends to make it work. COllector was made in house and tailpipe was from some muffler shop bends with a CR125 rubber anti-vibration mount.
Hondas seem to work best with long megaphones and the old race kit megs were too short. That one looks short, but try it. Go with a short tailpipe before the megaphone that is suitably larger than the primaries (headers).
I recognize that nice looking 68 sloper in a 64 CB160 chassis, with CB200 head, VM26 carbs and crank mounted Dyna S. It's one I built and it's still in the garage last time I checked. Headers came from a cheap swap meet 400 Bandit 4 into 1 that provided enough bends to make it work. COllector was made in house and tailpipe was from some muffler shop bends with a CR125 rubber anti-vibration mount.
