Topic: cb750A / now E! drag bike dreaming,

[Don R]

 If a guy was doing some covert chassis work anyway to a 750 frame for Drag racing would you increase the rake a little? Maybe two degrees? Combination of a wrecked F and abandoned A frames.
 We've front halved two alky funny cars and built a new cage/seat for one so the tube work is a no brainer.  I built a Hossfeld type tube bender also but don't expect to use it.

[dragracer]

If a guy was doing some covert chassis work anyway to a 750 frame for Drag racing would you increase the rake a little? Maybe two degrees? Combination of a wrecked F and abandoned A frames.
 We've front halved two alky funny cars and built a new cage/seat for one so the tube work is a no brainer.  I built a Hossfeld type tube bender also but don't expect to use it.

I see no reason to rake the front end of a street bike. I did rake my F3 a few degrees when it was built in the 90's just to clear the sidewinder but I was running the stock 19" Comstar wheel at the time. I now run an 18" wheel and shorter profile tire. On the F1 I'm building, I did not rake it at all and installed an 18" wheel. I have lots of clearance between the pipe and the tire. I wanted a longer wheelbase on this bike but current wisdom dictate's a longer crank to axle distance versus, axle to axle. A longer crank to rear axle allows the suspension to work better to decrease 60' times. Weight is transferred to the rear tire more efficiently without causing the front end to rise.  Be certain to lower and stiffen the front forks to minimize travel also.  More rake will only make the bike steer heavier at low speeds although it does assist with higher speeds stability. But that's what a quality steering stabilizer is designed for anyway. So I would suggest investing in a stabilizer and a longer arm with good shock absorber's versus raking the frontend. But what do I know 😊.

[Don R]

  The question is, if you were cutting and welding anyway for a drag bike not "would you" but how much would you? The titled F is already cut up (it saved another frame already)  and stashed in the corner waiting for a donor frame.  A mix of two was what I always planned for a custom.  I have other bikes for the street and normally go to the drag strip 12-14 weekends a year anyway.
  I am listening, I already got 12" koni's and a long clubfoot swingarm that I intend to modify to swing. A stabilizer will also go on, waiting to see if we have one in storage. My existing K dragbike has a lowered front end, new tubes and double bronze bushings inside. My Shinko on an A rim is however a drum brake deal, I'll need to re-lace it for the disc. 
 I previously made a composite fork brace, I sold it on the bike but would make another if I can source the materials again.

[dragracer]

I'm sure you'll figure out the path forward that works best for you. Good luck with the project. I hope when you get it finished you'll consider making a few of the Man Cup races with us.

[Don R]

 I have to admit I'm a little envious of you guys, normally my Super Comp racing eats up most of the summer but we took this year off after the driver having a baby and the engine having a cracked head. That gave me some time to work on bikes.

[dragracer]

I have to admit I'm a little envious of you guys, normally my Super Comp racing eats up most of the summer but we took this year off after the driver having a baby and the engine having a cracked head. That gave me some time to work on bikes.

Don't be envious, be a participant. With all the money you've probably saved not racing the car,your current stash should be big enough to make the world finals in November to help the rest of us celebrate the 50th anniversary of the 750 and the potential debut of the rebuilt RC top fueled.

[NitroHunter]

I believe the old DRAGBIKE rulebook allowed 36 degrees with a stabilizer and steering stops, so that was what I did. Back then pretty much what we all did for a racer. Extremely stable in a strait line especially at very high speeds, but quite a different cat riding around town. Just imagine riding (leaning) a long wheelbase chopper - with very short forks. Turning radius sucked but I was never a fan of twitchy sport bikes so it suited me. Also nobody dreamed of crazy long swingarms that are so common today, 6" over was a big deal to have made. You are a pretty talented guy so whatever design you initially build doesn't have to be the end result, enjoy the journey. 

[dragracer]

For a good example of how drag bike technology has changed over time, go to the XDA site and look at some of the pro street bike pictures. Those bikes exceed 200 mph as a rule, not an exception. The frames are short necked and deraked.  The arms are very long to handle 500hp on a street treaded tire. Once again, the bikes are typically DERAKED on these high horsepower bikes. The seating position is as far forward as possible to put rider and engine weight mainly over the front wheel. The rear suspension is  carefully set up to then allow weight to transfer to the rear wheel without shocking the tire or causing rapid rebound. The days of strut suspension have long passed on a no bar bike. Custom built shocks are designed specifically for your application if you're willing to pay the price. I spoke with Marcus Mc Bane at M2 shocks about a custom set for my CB. He watched my bike launch a few times to determine how the current suspension was responding and said the shocks I had were working fairly well but he could set me up with a more optimum design.
 

[Don R]

 I got the Super Comp heads repaired and new valves put in. The last few seasons the car actually broke even on fuel and entry fees. We should go NHRA racing, it's just too many days at the track. Our association has two races per weekend and starts paying at second round loser. Win 3 rounds and you break even.
  I'm leaning into just getting the old drag bike going, even if it's a stock motor. I'm down 25 pounds now, getting close to my old car fire suit fitting. I'm rambling, it must be late. 

[NitroHunter]

Wow Don, anytime you break even running a dragster it's a win! 
Rock the Stock and have some fun. 

[Don R]

  Thanks, I've been pretty pleased with our racing the last few years, we've been in the top 5 in our association when I keep the engine healthy. My buddy and I back halved our 1991 car, got a 6.0 cert and it's been working great.  My driver kills the tree and tightens up the stripe pretty good. I'd like to think I can learn it after I taught her. LOL.
  I pulled the old dragbike motor today and will attempt to make it run.  I want to build the F'nA frame this winter when we have more time. I think the A had issues, I see signs the PO was digging in the trans. Permatex on gaskets and stripped screws.
 

[POPS 911]

All I heard about was a CB750A that ran 10's in 1320'. Watched CHAD win many rounds on his Hondamatic 750 at IDBA and PRO-STAR and he never ran 10's = he is a big ol boy. I offered the fellow who said he ran 10's gas money and I would pay his get in the gate at my home track in Columbus Ohio  the offer is still GOOD. I won KING OF COLUMBUS with a  dead on the DIAL, rt.o3 against the ST/ET track Champion,HOLLOWEN HOOT, NIGHT UNDER FIRE, MANY WEEKEND ST/ET and Wednesday night races on a HONDAMATIC = 400CC, It's called BRACKET RACING.

POPS BK911 NHRA

[dragracer]

Pops, I'm sure we'll get to see a 10 second auto pass sometime in the near future.

[POPS 911]

FRANK: After seeing the HD NEW ELECTRIC bike I asked my lady = BUY ME ONE, HER ANSWER WAS WITH ALL the frames and parts for a 750A you have pay to have JEGS build you a 750A ELECTRIC DRAG BIKE [ NO MORE KICK STARTING after 30 years ] = They JEGS built a few JR. Dragsters that run at our track and are tuned with a lap top..... let's think no gas, no oil , no spark plugs, no weather station [ use a WIND SOCK ] and a battery charger. Like I said it's a bracket race and run your dial in every time will get you a win ticket. My birthday is the 19 Sept. and at 77 years old this might give me a few more years on the 1320'.

POPS BK911

[Don R]

 Pops, you're not the first guy to notice the electric jr dragster kit that jegs sells. They adjust the ET for the beginner to older kids by adding voltage. I'm afraid if an electric bike was too good they would make a rule against it like they tried with the A's at some tracks. Do any of the existing electric bikes have a gear change?

[Don R]

 The electric conversion kit for a jr dragster runs 7.90's in the eighth mile reportedly at 50% power. Costs $9167.92 I'm not sure if it runs a clutch, there is a jackshaft for sure.
  I can't help wonder if a conventional 1500 amp gel battery pack in a suitable container that may be swapped between runs would save a large chunk of money.

[Sam Green Racing]

The electric conversion kit for a jr dragster runs 7.90's in the eighth mile reportedly at 50% power. Costs $9167.92 I'm not sure if it runs a clutch, there is a jackshaft for sure.
  I can't help wonder if a conventional 1500 amp gel battery pack in a suitable container that may be swapped between runs would save a large chunk of money.

Don, EVs don't need a clutch or gearbox.
When the bike or car is at a standstill, the motor is not running, it only starts running when you open the throttle, so no need for a clutch.
In respect of the gearbox, EVs have that much torque, they will pull from a stand still to whatever speed they are geared for.
The bike I had was geared for 100mph, twist the twist grip to quickly and you end up being spat off the back.
When it reaches the speed that it is geared for, the acceleration stops that quickly, it's like hitting a brick wall.

Sam.

[POPS 911]

I Went to the oldest Harley dealer in USA = A.D.FARROWS in Columbus, Ohio to see this Electric  HARLEY , will have one in showroom 2020 . You should go to a HARLEY dealer and look at the display [not the bike] I don't think I can find a special CORD long enough to reach from THEIR HD charging stations to our local track [ they have a map with the charging stations locations about 35 miles away ] JEGS EV JR. Dragster you just use your generator or the tracks 110V plug in to charge. Good news is they Harley have a charging station in Yellowknife Manitoba CANADA . Does Honda make a battery fork lift ? I could get that motor and my HONDAMATIC could be all Honda powered = bet FRANK could build that 1320' racer. Talk to a TESLA owner about their travels from station to station like trains of old days water and fuel.
POPS BK911

[Tintop]

Talk to a TESLA owner about their travels from station to station like trains of old days water and fuel.
POPS BK911

What a great comparison POPS!   Mind if I use it?

[bear]

The electric conversion kit for a jr dragster runs 7.90's in the eighth mile reportedly at 50% power. Costs $9167.92 I'm not sure if it runs a clutch, there is a jackshaft for sure.
  I can't help wonder if a conventional 1500 amp gel battery pack in a suitable container that may be swapped between runs would save a large chunk of money.

Don, EVs don't need a clutch or gearbox.
When the bike or car is at a standstill, the motor is not running, it only starts running when you open the throttle, so no need for a clutch.
In respect of the gearbox, EVs have that much torque, they will pull from a stand still to whatever speed they are geared for.
The bike I had was geared for 100mph, twist the twist grip to quickly and you end up being spat off the back.
When it reaches the speed that it is geared for, the acceleration stops that quickly, it's like hitting a brick wall.

Sam.

Sound's a bit like my mobility scooter.

Cheers,
Brian

[Sam Green Racing]

The electric conversion kit for a jr dragster runs 7.90's in the eighth mile reportedly at 50% power. Costs $9167.92 I'm not sure if it runs a clutch, there is a jackshaft for sure.
  I can't help wonder if a conventional 1500 amp gel battery pack in a suitable container that may be swapped between runs would save a large chunk of money.

Don, EVs don't need a clutch or gearbox.
When the bike or car is at a standstill, the motor is not running, it only starts running when you open the throttle, so no need for a clutch.
In respect of the gearbox, EVs have that much torque, they will pull from a stand still to whatever speed they are geared for.
The bike I had was geared for 100mph, twist the twist grip to quickly and you end up being spat off the back.
When it reaches the speed that it is geared for, the acceleration stops that quickly, it's like hitting a brick wall.

Sam.

Sound's a bit like my mobility scooter.

Cheers,
Brian

Spot on Brian, hahahaha, but the bike I had, although it looked a bit strange, would rip your arms off. haha.

[Medyo Bastos]

Big Pimp’n Sammy


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[Sam Green Racing]

Big Pimp’n Sammy


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hahahahahha.

[dusterdude]

The electric conversion kit for a jr dragster runs 7.90's in the eighth mile reportedly at 50% power. Costs $9167.92 I'm not sure if it runs a clutch, there is a jackshaft for sure.
  I can't help wonder if a conventional 1500 amp gel battery pack in a suitable container that may be swapped between runs would save a large chunk of money.

Don, EVs don't need a clutch or gearbox.
When the bike or car is at a standstill, the motor is not running, it only starts running when you open the throttle, so no need for a clutch.
In respect of the gearbox, EVs have that much torque, they will pull from a stand still to whatever speed they are geared for.
The bike I had was geared for 100mph, twist the twist grip to quickly and you end up being spat off the back.
When it reaches the speed that it is geared for, the acceleration stops that quickly, it's like hitting a brick wall.

Sam.

Sound's a bit like my mobility scooter.

Cheers,
Brian

Spot on Brian, hahahaha, but the bike I had, although it looked a bit strange, would rip your arms off. haha.

Who's the old guy?

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[RAFster122s]

There is an old guy in that photo? I see a strange bike and pair of young ladies...