I have a Echo / kioritz 21.2cc GT-200R
Bore is 32.2mm / 1.27 inch
stroke is 26mm / 1.02 inch

Timing is:
Exhaust after top dead center 118 degrees
intake after top dead center 67 degrees
exhaust duration is 124 degrees
intake duration is 134 degrees

any ideas on redoing the timing?
i bet i can get so much power out of this beast to make woodys blata tuck its tail and hide

some mods that some one made to one of these motors
www.rcuniverse.com/forum/m_581.../tm.htm#5811152

Thanks every one

Are you sure about the intake and exhaust numbers? They seem odd? I'm absolutely no specialist of these though... I'm sure Scott has seen them and can guide you in the right direction when he sees this post.

Your topic on modified echos was nice... but after talking to a man at our local hooby shop, he breaks his Zens in with an 18 X 8 APC prop. I used this technique on my Chung Yang 27's, and at the end of the first gallon, I was spinning an 18 X 6 flopping just above and below 14,000!!! I do alot of conversions on plane (my first love) engines myself... and I've found myself, doing mods I'm capable of, none of them come close to my 26cc Zen airplane motor. I've done all the tricks they talked about in the article, if you know a secret they're not telling, PLEASE let me know!!! I have about 25 weedeaters laying on my garage floor just waiting to be reworked!!! BUT FIRST>>> I must finish my KILLER KAT!!!!!

goesman wrote:
Don't really have much to say in modifing any of the SRM200 series Echo's due too so little success in actually getting them to wake up, this for quite a few known reasons. (Srm 200, Gt200 and a bunch of sub models are all within that series)
Cylinders cast VERY MINIMAL in material in and around the basic shape as cast being very limiting on opening up passage sizes enough to actually get flow volume increases sufficient enough to make a difference , exhaust port height, transfer passage area and port sizes cast VERY conservative in size.
It also became obvious Echo specs on coils had RPM limiting governing and seemed no mater what we did 11K rpm was a wall no matter what specs we got away with grinding away on ports.

Not too sound the killjoy ... but that series engine was designed as a 2000+ hour @ 1.2 HP utility weed wacker engine that just does not have much potential because Echo built them so purpose specific.

Man Scott your like the Yoda of small engines. The more i look this little motor over the more i see that it lacks in areas that it should not. But i would like to still see what i can do with it even if it is highly limited. I have already put a larger carb on it and noticed a difference in how it revs up.

All the timing numbers are spot on i checked them several times.

Thanks

By all means carve away and learn what you can. My intent was not in stopping your playing around but more of getting down to the mater of fact reality of findings many have found before you without the fluff.

I worked as a commercial 2 cycle engine tech doing professional lawn and garden and logging size and grade chainsaws from @ 1977 to 2002 .... yea, been there and likely tried that

I know all about chainsaws, i do some logging and own a sawmill that i mess with on the side right now.

I will see what i can do to the little motor, i just didn't want to screw some thing up and make it not want to run.

Right now i have a WT231 carb on my motor, not sure what size that is. I was wondering if a WT257 would be to big for 21cc

Thanks

goesman wrote:
IMO it would be too large .....

Ok, i was just wondering.
Thanks