Ruttman Spyder build

#1
Hi guys- I'm new here and really enjoying all your knowledge! I got bit by the Ruttman bug this summer and now on my second build- this one's for my wife. I picked up a roller Spyder with bad bicycle handle bars. Also found an HS50 and cleaned it up to reconfigure for a mini bike:

20191016_211714.jpg 20191030_211151.jpg
 

markus

Well-Known Member
#6
Looks good, whats the thinking with the throttle setup? Is the governor removed internally? I can show you how to get more travel out of the throttle control (they come incorrectly setup for recreational throttle control). Did your original carb have adjustment needles, If so would you want to get rid of it?
 
#8
Looks good, whats the thinking with the throttle setup? Is the governor removed internally? I can show you how to get more travel out of the throttle control (they come incorrectly setup for recreational throttle control). Did your original carb have adjustment needles, If so would you want to get rid of it?
The throttle setup I am using is a copy from this article:
http://www.pinrepair.com/minibikes/tecumsehmb.htm#intro

I did remove the governor internally so I am using the old governor rod to actuate the throttle. If you have a better way, I'd be interested to see. The old carb was the snowblower carb, and didn't seem to have needles. Just the adjustable idle circut and main jet. On the new carb, I bent the throttle limit tab so I get full open on the blade - is there something else I should look at?
 

markus

Well-Known Member
#10
The throttle setup I am using is a copy from this article:
http://www.pinrepair.com/minibikes/tecumsehmb.htm#intro

I did remove the governor internally so I am using the old governor rod to actuate the throttle. If you have a better way, I'd be interested to see. The old carb was the snowblower carb, and didn't seem to have needles. Just the adjustable idle circuit and main jet. On the new carb, I bent the throttle limit tab so I get full open on the blade - is there something else I should look at?
Heres what can be done to make those late model throttle controls easier to work with and gain more travel: https://oldminibikes.com/forum/inde...mseh-carb-throttle-linkage-on-small-h.147588/

I'm not a big fan of the solid linkage going across unless your measurements are super precise, at some point its going to get pulled on harder than it should at full stop or full open. Plus if its there to override the governor if not done correctly it will cause internal issues with those parts (in your case that's irrelevant but I've thrown that in for other people looking at this thread for reference in the future) . On yours it almost looks like the solid rod has some bends which may cause going out of adjustment due to movement/bending. The spring run to the Governor pivot shaft may also cause more wear on case/ pivot rod, since its being pulled on constantly.

Too bad on the OG carb being fixed needle. Slight alterations (or even just using the primer nipple as an overflow tube out and away from paint thats not fuel proof) make for a great carb when serviceable. Plus you get the correct bore and idle circuitry internally so its usually a smoother more reliable operation if your keeping it a tame basically stock engine.

Heres a thread I did on how I convert those type carbs when I find them, if you get more into these down the line it may come in handy:
https://oldminibikes.com/forum/inde...rs-to-mini-bike-application-hs-series.164438/
 

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