Author Topic: Performance prediction. Stock engine on a no bar dragbike frame  (Read 2459 times)

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Offline Don R

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #25 on: February 05, 2024, 04:31:15 pm »
 Here's my version. I have a low mile F2 engine that needs torn down and cleaned since it sat with the top end off before I got it. It now has an A front rim and new tire. If I ran that mag I could leave the battery and starter off of it and run a really cut down flywheel.
« Last Edit: February 05, 2024, 04:35:21 pm by Don R »
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Offline dragracer

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #26 on: February 05, 2024, 09:42:11 pm »
Here's my version. I have a low mile F2 engine that needs torn down and cleaned since it sat with the top end off before I got it. It now has an A front rim and new tire. If I ran that mag I could leave the battery and starter off of it and run a really cut down flywheel.

Thats a good start Don. I've always been curious as to how quick my 1030cc engine would go on a properly set up wheelie bar chassis with a small slick. Throwing a clutch  off a 2 step at WOT with no worries about a wheelie or spinning- priceless.

Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #27 on: February 06, 2024, 08:02:10 am »
Frank, I like the idea of the single switch of going to high compression pistons and the following comparison results. I'm sure that would wake up my 915. Thinking before or after cam? 
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline 1080

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #28 on: February 06, 2024, 09:03:40 am »
Clutch? Stock( very poor in drag racing) or Barnett clutch much needed.

Offline dragracer

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #29 on: February 06, 2024, 10:42:58 am »
Clutch? Stock( very poor in drag racing) or Barnett clutch much needed.

Stock clutch set up has always worked well for me. I'm a "never Barnett " kind of guy.

Offline dragracer

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #30 on: February 22, 2024, 09:30:36 pm »
I completely forgot about this F model roller i have storaged inside one of my enclosed trailer. It was given to me by the family of a deceased friend.  I helped him buikd this bike a few years before he passed away. We pulled the stock engine because it was puffing a little smoke. I think I'm going to completely freshen up the stock engine and use this bike as my test mule. I can slowly build this one into a more realistic performance engine as the average forum member would to show changes in drag strip improvements with each step.  No need to let rhe bike sit and deteriorate when it can serve a purpose.

Offline Don R

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #31 on: February 23, 2024, 12:25:54 am »
 That's a great start, I spy some chassis improvements already done, forks and front brake, 1/4 fairing, long swingarm, and lighter rims. Is that a V&H header?
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Offline dragracer

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #32 on: February 23, 2024, 03:43:41 am »
That's a great start, I spy some chassis improvements already done, forks and front brake, 1/4 fairing, long swingarm, and lighter rims. Is that a V&H header?

Don, you are correct in your description of improvements.  We found this bike in a back yard where it had been laying on the side for many years.  It was rusty, crusty and grimie. We tore it down to the bare frame and started making ipgrades like retrofitting the oil cooled GSXR 1100 front end, added the Katana 600 mono shock  swingarm and used Hayabusa wheels.  The engine was toast with a broken camshaft, welded together cases and other issues so i cobbled together an engine from various parts i had laying around.  The fairing was added later but I'm not particularly a fan of this one. Yes, thats a new V and H sidewinder that i bought for the bike. I had to piece together a wiring harness for it and added an electronic speedometer and tach. My friend painted it and had the seat down. The frame was powdercoated. The bike ran pretty good once we sorted out some carburetion issues from the PD's. It started puffing a little smoke after a while. I think we had a bad vallve guide as we didn't freshen up the head like i normally would have on a fresh build. I got the head used and it supposedly had a recent valve job. So much for that story. Nevertheless,  it'll go back up with all new parts and a fresh head rebuild. I'll just need to add an airshifter and a shift light before trying to race it.

Offline Don R

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #33 on: April 03, 2024, 10:28:55 pm »
Any progress on this one?
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Offline dragracer

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #34 on: April 04, 2024, 07:10:40 pm »
Any progress on this one?

Unfortunately nothing has been done since i posted last. Race and gardening season snuck up on me so building an engine in atockbtrim has taken a back seat. Once i get settled in with ourvrace program, my intention is to begin turning wrenches on this project. I'll need to retain my focus as i move along and not be tempted to build a "hot"" engine.  I want to be able to compare stock motor ET'S versus a high performance build. My only deviation is to put on rejetted csrbs to match the sidewinder exhaust flows. I may have the transmission undercut for reliability.

Offline Don R

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Re: Performance prediction. Stock engine on a no bar dragbike frame
« Reply #35 on: April 05, 2024, 09:56:42 am »
 I hear you, I've also got a few projects waiting for my time and energy. I can say that we're lucky to have them.
  My connection to mechanical things began with skateboards, bicycles, then slot cars, then real cars, then motorcycles, Drag Racing, then a blend of all of the above. My brother said that one day our sister had street skates and a toy ironing board, the next day I had a skateboard.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.