V-Twin Board track racer

GoldenMotor.com

Tom TG

Active Member
Dec 10, 2012
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28
Oklahoma
Rick the rocker arm needs about a 1/4 inch more clearance. Its that darned hi lift cam . I may be able to mod the rocker and get the clearance I need.
The 3D clutch is going to take some redesign to fit my 1 inch crankshaft very few original parts will be left of it .
I need it on the crankshaft because I am going to put a one way clutch on the peddle shaft and that leaves no room for the clutch.
I left room on the rear hub for a future brake.
I plan on putting a compression release on one cylinder.
Here is a picture of the engine in the frame you can see the valve problem the valve is down.
image.jpeg image.jpeg
 

indian22

Well-Known Member
Dec 31, 2014
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I've suggested to the 3-D guys that a clutch for the 1" shaft be a priority in their product line as well as adapter bushings for the smaller diameter straight shafts. They had this in mind and advertised they were working on a 1" clutch many months ago but dropped the project along the way. There's a Utube video that shows an 80 hp cart using the 3-D clutch and it's hauling! 3-D used to post that link on their website as well but it's been taken down. A one inch shaft clutch would sell to those that are contemplating large V-twin Predator and Briggs style motors. I'm glad to see you tackle the problem, though 3_D should have had a clutch on the shelf for the purpose!

Thanks for the photos. To me the bikes stance is perfect & really frames the engine well. Single cylinder compression release seemed to be the preferred solution back in the day. The rocker clearance is pretty clear also. Even with the clutch mounted on the engine the profile when viewed from the front should still be quite narrow and proper thanks to the narrow crankcase design.

Enjoy the beautiful weather we're having here in Indian Territory, lol. Rick C.
 

indian22

Well-Known Member
Dec 31, 2014
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Tom I''m liking the bars and riser's look also...they go well with the fork and wheel. I've no doubt the drive will turn out also. Rick C.
 

indian22

Well-Known Member
Dec 31, 2014
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Tom I went back to your V-twin motor build thread and read it again last evening & greatly enjoyed it. It's a shame the photos were lost due to photo buckets fiasco. It would be wonderful if you could post a few photos that show some of the skill employed in building your own V-twin engine. I'm not sure that some of the readers of this thread are yet fully aware that you machined and designed this engine without blueprints, in your mind. Some photos of your single cylinder motor (also self designed) & bike would also help us all to fully appreciate what you are currently doing.

Your two engine builds, and the bikes they find a home in; display, to my mind, the most intricate design, while presenting the highest level of difficulty and the best overall execution of fabrication of any build ever seen on this forum, even though there are a lot of fantastic bikes that I'd be proud to own displayed in various threads, you sir are currently working in a league of your own, and that is inspiring! With respect, Rick C.
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
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Just amazing build thread. Earlier you mentioned something about pedal crank arm length. Since you plan to pedal start the bike and it's a boardie, which is a very tight riding position, I would suggest making sure you have enough room to pedal while seated. The longer the arms the more flex you need in your knees to get over the top of the pedal stroke. I have used a few different arm lengths over the years. It's not too critical on a cruiser with it's higher seat position, but I always use shorter arms on a boardie. Regardless of crank arm length pedal starting a boardie can be a challenge. Better to park at the top of a hill instead of the bottom if you know what I mean.
Pat
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,844
485
83
california
Just another thought with using a manual clutch on a single speed bike, and I know this is probably obvious but still worth mentioning, it's better to gear the bike for more bottom end. Tall gearing is harder on the clutch and harder to start the bike.
 

indian22

Well-Known Member
Dec 31, 2014
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Tom thanks for sharing these build photos with us. Having both the motor and bike build in the same thread just helps all of us get our heads around the task you set for yourself. Amazing work!

Pat's dead on as usual about the drive train, manual clutch & pedal starting..gravity is your buddy on start ups...and your compression release as well. It helped that the early bikes had manual ignition on starts as well. Rick C.