best motor for a custom street bike

[toydoc]

Hi what do you mean going the right way? I see the carb and pipe are on the same side. I want this to look like it came from the factory. I also need electric start so we can get rid of the pull cord.

If your going to make a real race bike, this lets you drop the CG. The ONE exhaust can tuck and rout right through the wishbone, never pointing out the front.
With the others, your making a Honda CBX two stroke with no place to run pipes.
You really need pipe measurements to go with your motor deal. I would guess most will need 1.2 ~ 1.4x the motor area A = a2. That said bolting a motor in wont be a issue, finding room for all the pipes will take some time

 

[dopaytoplay]

Here is a few 3 cylinder pipes idea's I have. If we have to we will use a two stroke twin and have the pipe's cross over before they go back. I'm old school as I like to see the motor and pipes. This bike will have a fairing just not a full fairing.
Jay

 

[dopaytoplay]

Here is the frame style we might use. This guy lives right by me also. I can't see why you would want to hide this with bodywork. I would also be using better forks and wheels. We also would use a swingarm like a aprilia tuono or rgv 250 Suzuki banana arm.

 

[opsled]

A couple things to consider about using the inner half of an OEM clutch is that it's ring gear and starter are about 8 " in diameter and the ring mounts at the outer 7" ring of that diameter. The starters mount to the forward side of the engine some using the engine mounts and not the crankcase to hold position. They are all of an open design and are visually very unappealing in my opinion. You may also run into issues with mounting your trans drive gear to that inner clutch. If you were to key or pin the gear onto it you may need to turn it's diameter down and there is not a lot of meat to do so before you get into the inside taper bore.

The UL (ultralight aircraft) division of Rotax (Ski Doo) has a 90* e-start system that replaces the recoil starter with a cup style ring gear and starter that is at 90*s to the crank shaft. That system is a bolt on to many Rotax snowmobile engines and could be adapted to may others including other brands. I think it would be better looking than stock snowmobile open systems and easier to hide under a partial fairing.

As I said earlier if your buddy had an E-start option that could be incorporated into his trick trans it would simplify the whole concept.

opsled

PS, I like what you are doing and am enjoying the pics. Thanks!!

 

[dopaytoplay]

A couple things to consider about using the inner half of an OEM clutch is that it's ring gear and starter are about 8 " in diameter and the ring mounts at the outer 7" ring of that diameter. The starters mount to the forward side of the engine some using the engine mounts and not the crankcase to hold position. They are all of an open design and are visually very unappealing in my opinion. You may also run into issues with mounting your trans drive gear to that inner clutch. If you were to key or pin the gear onto it you may need to turn it's diameter down and there is not a lot of meat to do so before you get into the inside taper bore.

The UL (ultralight aircraft) division of Rotax (Ski Doo) has a 90* e-start system that replaces the recoil starter with a cup style ring gear and starter that is at 90*s to the crank shaft. That system is a bolt on to many Rotax snowmobile engines and could be adapted to may others including other brands. I think it would be better looking than stock snowmobile open systems and easier to hide under a partial fairing.

As I said earlier if your buddy had an E-start option that could be incorporated into his trick trans it would simplify the whole concept.

opsled

PS, I like what you are doing and am enjoying the pics. Thanks!!

This is what I like to here! My buddy's transmission is based on a Harley but he took 5 inches off the length. We will check out if we have the room Harley starters are big and ugly!!

 

[dopaytoplay]

Here is few pics of the bikes he builds. The dirt bike he built for a old big fat guy that jumps cars.

 

[dopaytoplay]

Hey guy's
I still need the measurements of the srx700 motor (top to bottom, side to side without the clutch, and front to back with and without carbs on it.
Thanks Jay

 

[dopaytoplay]

a few more pipe pics

 

[Whammy]

well ya

 

[780srxgeorge]

all right wheres the up dates?.i would like to see a sweet bike w/ a srx motor.shoot i would trade my srx & my 2 bikes,a 99 yz400f & 00 drz400.that kaw triple is very very nice would LOVE to ride that bike.so keep up the good work!!.

 

[opsled]

Google Yamaha GL750. It was a prototype based off the TX chassis using a street version of the TZ750 4 cylinder two stroke.

Cool bike. If it were built the H3 Kaw would have seen nothing but tail lights.

opsled

 

[Whammy]

72 tx,,,,2 cylinder ....