Hi Guys,

planning to buy a CY 26 that is apparently running 18,000 RPM and is rahter well priced. I am not very experienced with Gas boats so any feedback on this engine/brand is welcome.

cheers
Andre

The feedback I have mostly heard is that these engines' reliability is questionable when they are modified much. I have never owned one myself, so I can't confirm, but Scott Schneider might chime in as he has owned and modified some.

I have however run some in stock form (loaners), they ran ok, but I hated the fact that they will not crawl to a start line like a good Zenoah will. They are more powerful than Zens in stock form however. Modified, I think the Zenoahs are the way to go.

Can you post a link to this 18k CY you are talking about please? I would be interested in seeing who it's from.

Yes, the CY 26 marine I fooled with for a few years was run maybe 3 gallons of fuel.

In that time the original cylinder had the soft chrome and was trashed, Did a 27cc 35mm jug that ran pretty well and was only a tester and illegal to race with so I sold it off the engine. Did another full mod 25.4 top end next and it failed within a gallon of fuel by splitting the casting at cylinder base. Did another top end with more mild mods and it ran less than a gallon before warping the cylinder base and spitting out gaskets one after another.
Finally put another NEW top end on it and SOLD IT !!

Lets say at this point you would have to PAY ME to own one and would only do so with more than one because they IMO are too unreliable

The broken one

I just finished some dyno tests on a Chung Yang 27 ported for SAW racing. The engine made over 40 dyno runs at up to 24,000 rpm. It developed good power, especially past the peak. SAWs require very high rpm since propeller pitches are limited. The main problem was the two cylinder bolts wouldn't stay tight. We finally replaced the stock base gasket with an aluminum one and safety wired the cylinder bolts. The next engine will be built without a base gasket.

A tear down showed normal break in wear. I expect the cylinder cracking and gasket failures come from loose cylinder bolts. We were able to see the failure immediately and brake the engine quickly to a stop. At the very least, I would use a copper base gasket and locktite the cylinder bolts. Safety wire, properly done, is even better. The best solution would be a four bolt cylinder.

Some testing with another Chung Yang engine using the 36mm cylinder and a 2mm stroker crank didn't do as well. I need to rethink the porting since the engine isn't going to run at the rpm of the shorter stroke engine. For now the 27 seems to be the best choice for a NAMBA G2 engine. I'm surprised it's not more popular.

Lohring Miller

Thanks a lot for the feedback guys. I think this engine is a good low cost weekend racer until i have more hands on experience to get serious about speed. I am a hardcore high performance EDF jet junkey and really enjoy boating as a 2nd line of RC addiction.

Here is the requested link, be aware that some of the boats from Arrow Shark are old models and therefore less expensive. Singapore is in general less expensive for RC gear.

www.jethobby.com.sg/cgi-bin/ez...48&idx=11&gid=6

What is considered a good source for a affordable and easy to handle yet decently modified Zenoah?

I just check out that link. As far as I can tell that motor is a stock motor they are selling. Is the $450 price in USD??? CC Racing have this same motor on their site for $250!

Here is the link: www.cc-racingengines.com/index...7e2b7503a0a05ec

They also sell Zenoah engines. There are several other vendors on this site that sell modified engines.

i would be carful with the sikk ,c/y motors i had one and i went and replaced the pull start 4 times as thay are a real pain in the starting department change it to a zenoah pull starter with a aluminium spool.

also be carfull where did you find that company listed from????.


looks like its listed in singapor dollars????...or mybe not . if that us that is way to much . they sell in australia for 280..austdollars..

for good starting ezzy to run motor idd go for a zenoah ennyday over the sikk. ive tryed them and only like it for the first day then hatted the experance i had with the starting and non low iddle that thay dont seem to have .
and ive seen more pics of brocken jugs in the same spot from the sikk then ive ever seen from a zenoah.......

450 is Singapore Dollars (around 1.55 Sing per USD). the shop is well known to me, nothing very special, just another shop on the block, been the only guy who brought in gas boats. I have already found sources in the US to buy that motor for USD 250 !

I ran a CY 26 last year for for fun,just stock old pipe- ran ok until it took a drink of water and lifted the cly right of the case! Stick with "Z", you cant go wrong.