Cylinder fin isolators

[soonerbillz]

Who sells the best quality cylinder fin isolator rubbers and what is the correct way to install them?

[Striker1423]

Yambits ones are a good and tight fit.
https://yambits.co.uk/rd350-barrel-head-rubber-dampers-p-12701.html

As for install:
https://www.aircooledrdclub.com/smf/index.php?topic=49063.0

They are pressed into the heads and the side fins of the cylinder. The head rubber pieces are connected by a thin strand of rubber in the middle, so they fit next to each other evenly spaced through the head fins. I used pictures from other stock RD's to match them up.

The long black rubber dampers get pressed into the two long fin breaks on the cylinder side. But just far enough for them to hold tight. Typically you'll see them sitting almost flush with the side of the cylinder fins. I made the mistake of pressing them on 'til they bottomed out. They still help some, but the sides ring a bit more than the heads as that end of the fin is where the vibrations resonate. A few heat cycles later and mine wont hold on the outside anymore.

Also, if you have bent outer fins, either fix them, or be prepared to cut a part of the rubber off.

[soonerbillz]

Thank you.
I see Yambits claims those are not for USA RD bikes.
But the Air-cooled post mentions that the USA RD differs from the R5 cylinders and heads in the casting. I assume then that these would work for me on my R5?

[Striker1423]

It says not for the 250, but I highly doubt that. The dampers would fit in either fin.

[SoCal250]

Economy Cycle - Head Rubber Damper Kit, RD250/RD350/R5/DS7

[m in sc]

fin count, i think, is different on some 250s if not all (not an expert on 250s).

that being said, you could just cut one off.

[soonerbillz]

I gotta fiqure there can't be too many folks making these things. So I'll assume quality is likely equal. I'll probably just buy them from John @ Economy.

[Economy Cycle John]

We send 20x of the head dampers with the kit and 4x of the cyl dampers. The USA 250/350 use 20x of the head dampers, the c/d/e 400's use 18. The head dampers are identical, the cyl dampers are specific to the 250/350/R5/DS7 and 400.

The USA F Daytona used 4 cyl dampers but they were unique to the Daytona and no head dampers. I don't carry those, not sure if they're available anywhere and if they were like the non usa F & G's.

The later 250's in europe were different and looked more like our 400's so that can be a bit confusing when looking at yambits parts.

As far as quality goes, sold them for years don't recall any complaints other then the head dampers are hard to get in, which is true, but that's the way it is, if they were easy to get in they wouldn't stay in.

[soonerbillz]

Thanks John..
I'll be sending you a order for more stuff soon.