Engine suggestion for speedway scarab

[Dubs]

Picked up an old speedway bike at a garage sale. Pardon the noob question, but what type of new engine do I need for the slanted mount plate?

I'm not looking to restore it, just want to have some fun with it. Can I put a bigger more adult friendly engine on it?

 

[sludgeboy]

Yes, its been done several times. Its the front forks that need attention or replaced.

 

[Dubs]

Can any engine be mounted on an angled mounting plate? Sorry for noob question - I just assumed the carb would have to be level

 

[capguncowboy]

Can any engine be mounted on an angled mounting plate? Sorry for noob question - I just assumed the carb would have to be level

You can mount just about any engine at the slanted motor plate, but you'll need to put a slanted intake on it to keep the carburetor level. Otherwise, it won't get the proper amount of fuel and the motor won't run.

 

[Dubs]

This slanted intake adapter ... can you point me to where I can find one? I'm going to be buying a new engine for this frame ... so if it needs a slanted intake, I'll likely be buying an engine that has such an adapter readily available for it. Sorry for all the questions - thanks for the help!

 

[joshua. c.]

what sise engine dose the bike curently have? if its a 3.5 or a 4 you coold upgrade to a tecumseh hs50 to get a bit more torque and it will still look right in the frame. also tecumseh carbs dont open fully in stock form. the carb only opens 3/4 of the way before the throttle stop hits the casting. if you grind it doun so the carb opens fully you will get a noticeable gain.

 

[Dubs]

After some helpful PMs from fellow members I'm leaning toward sticking with what I have on it and holding out for an ebay or craigslist 4hp Tec. Thanks all for the replies and PMs!

 

[joshua. c.]

the tecumseh hs 50 is the exact same size as the tecumseh 4 and looks the same but has more power. id go with a 5 horse instead.

 

[Dubs]

Good to know! My odds of finding one just got better! Right now I'm running HS 35

 

[Dubs]

I'm seeing a lot of older 5HP Tec engines on snowblowers all over craigslist for cheap ... are these any different?

Would seem to me the benefits are low hours, lighting coil.... but functionally are they any different?

 

[ole4]

A lot of the snowblowers are the big block H50 and it does not fit without trimming the frame. Also the side cover is out further than the HS series.

 

[markus]

I'm seeing a lot of older 5HP Tec engines on snowblowers all over craigslist for cheap ... are these any different?

Would seem to me the benefits are low hours, lighting coil.... but functionally are they any different?

For the HS50 size:

you will need to keep and eye on crankshaft size and match what you have (should be 3/4"), drilled and threaded crankshaft end is probably important for you application as well for TC driver , you want to avoid anything that has the 2nd pto shaft if possible (sometimes they utilize a shaft on the cam which can just be cut off but to me its just another seal/problem/moving part)

the snowblower HS50's also will not have a threaded exhaust port, so you will have to use an exhaust with a flange, and the intake port is an odd shape so you cant just bolt on an HS40 slanted intake to it.