(hush hush) Tweaking the Robin Subaru 35 for faster speeds

bamabikeguy

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Last night Mr. Cantor called, he's the 80 y.o. with 2 artificial knees, who chased me down on the last day of my NC trip. He ordered a 21 speed with RS 35.

He was thinking of ordering a second bike, selling the first one to a friend of his. But he wanted to know about getting more ooomph out of the Robin.

Then, about 6 pm, Jimmy Burke called, he's a MB.com lurker. He dropped off a Jaguar the same day as Mr. Cantor picked up his, test road Mr. Cantor's bike, and since April, he has 2,000 miles on his bike. He has a GPS installed on the Jaguar, to check everything to the 0.00001 decimal.

A friend of his also put a Robin on a Jaguar, both are superMB addicted.

Then they started tweaking.

When they finish analyzing the results, they will give me all the specifics, including item number.

But I thought I'd put up this preliminary thread, to get the ideas out there.

I talked to Denis at GEBE to discuss them this morning. He can't do this to his kits, because of warranties and such, but says "it works".

First, (AND I DIDN'T TELL YOU TO DO THIS) Jimmy removed his catalytic converter. He didn't touch the baffles, but used a dremel stone to clean it up, inserted a 3/8" nipple (locktited).

He says the increased compression could be felt 3 feet away from the exhaust, upped them both by 2 miles per hour.

Then they contacted, discussed and ordered two bigger carburators. This is where I'll get the product # later, but they cost $57 plus shipping (Denis said $55, I guessed $ 60 ).

The short story is, when they told the representative which carb was on the R/S, the rep. replied that size "acted like a governor".

We will wait for the road test results from Jimmy, but they are expecting more speed from the upgrade, with maybe a small decrease in m.p.g.

I spoke to my buddy Jack this morning, we MAY duplicate this on my recumbent soon.

(note the typographical error in my ad, I got a free week for their mixup)....
 

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cool ads there -- god eye catchers !!
been wanting to get a little more from my R/S
looking forward to hearing more about those carbs
going to take a look at my muffler -- if you know what I mean ??
thank you
from
MM
 
Why would Robin Subaru put a cat/con on an engine that already meets Tier 3 standards with out it?

More likely they removed the spark arrestor.
 
I haven't explored mine yet, if it is just a spark arrester (screen), that really is no biggie. I know there is a collar to hold that screen on the Zenoah's and Tanaka's, that must me what he used the drimel stone on, to push in the nipple.

Carb upgrade, maybe this Diamond Fire plug I noted in another thread, and a 14 tooth (not recommended) belt drive gear, I might get the recumbent in the 35-36 mph range.

http://www.google.com/search?hl=en&...,+spark+plug,+lowes&btnG=Search&aq=f&oq=&aqi=
 
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Any word on the carb upgrade? Part number or venturi size? I may have a carb sitting here that will work. ;)
 
Could be! I know that switching to an adjustable carb is easy. Which one is the question. I may have to go digging for info myself.
 
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