mods for the fs engine

[speedyd]

bob (a buddy of mine from largescalerc was over this weekend to check out a redcat that i picked up recently. while here we started talking about the fs engine. bob said he wanted to see an fs engine so i got mine out. (we came to the conclusion that bad bearing seals but the real surprise came when we opened the case it looks as though the port design looks to be better than anything cy makes, and they also look like they are matched better than even the 4 bolt zens.
i have heard that stuffed cranks will work in the fs engine. if the zen 4 bolt heads will work on these things, then look out we have just hit the mother load in power! i am a big fan of the 813 carb, so that will be my carb of choice. as for exhaust ive never seen or tried an fs pipe,but i have ran jet pro in the past with great results. if anyone knows of some solid mods/ upgrades please fill me in.

[fsmt4wd]

found this on the other forum from our friend asphaltcowboy:

Hi,
a friend tuned his FS engine with a CY crankshaft with 2mm more piston stroke travel and
a few more modifications, so he has now 5,4 PS / max 21.000 RPM measured on a engine test stand.
Yes, a DZY engine isn´t so bad ...

as for the pipe the tuned pipe works great(jp clone) i am looking at getting a rn tuning exhaust, they are a bit $$, i have heard whispers of a rn tuning clone pipe for the fs, nothing confirmed..

[speedyd]

yeah, i was hoping the ever allusive cowboy would see my post and throw in his opinion. from the looks of the ports they look a liitle more agressive than the cy or the zen.with some mild porting, good gaskets,and crank seals it looks like we might have a true power house on our hands. i will also be running a walbro 813 on it.

[hoppy]

hi speedyd...
sounds like you've already found the info you were looking for, but for what it is worth, Bryan from rcinnovations (New Zealand) has installed the Zenoah 4 bolter G270rc rebuild kit (approx $300AUD, from crank & bearing up to the head & everything in between) and he reckons she's a powerhouse, with no issues mentioned.
I've heard lotsa issues with the fs motor, from delamination, gudgeon pin, piston, bigend bearings, shaft bearings & seals etc etc, but i've never heard of crankcase issues...
I was contemplating the same on my fs motor after it self destructed, but i had already bought a zen g270rc complete with clutch & carb.
This zen in my fs onroad with new whitespot mcd tires & rims and standard gearing 30/33/25/24 was just no traction insane (see my vid)... yesterday i swapped gears to 33/30/24/25 and although she is much better to control, she will still start drifting sideways just under acceleration in a straight line lol
next weekend i'll be swapping the second 2 gears 33/30/25/24 so that might hopefully just be right for the power.
Just for interest yesterday my mate had his modded 1/8th running 25%... straight line he would have me off the mark, but only 3- 5feet on and i would round him up and hose him, to the point of serious embarrassment heh heh... he is now trying to strike a deal with his wife to go 1/5th ;D
while my fs motor was running, the carb seemed fine, being a walbro copy- and i must say, it really is identical from what i can make out to my real walbro, excepting the copy has a built in choke, where as the real walbro doesnt... personally i think better to do without the choke anyways... less venturi restrictions... i've also heard the walbro carb kit works with the walbro copy too
i've not tried any other tuned pipe other than the standard fs tuned... the only issue i had was i had to match port the exhaust flange (round to square), and given the power the zen puts out, i really dont want to extract any more power lol
i've heard some ppl have had leaky welds on the fs tuned pipe, but no prob with mine.
I know someone did a rally convert to the onroad and used a samba rally pipe which worked well.
hope this helps in some way

[speedyd]

hey hoppy, thanks that is what i was hoping to hear!

[hoppy]

no prob mate... feel free to contact Bryan with engine q's... i think i's rcinnovations.co.nz otherwise just google it

i am still contemplating doing the 4 bolt zen convert on my chinese crankcase... a good backup and wouldnt surprise me if it would quicker than my zen

[speedyd]

the next time you have a zen apart check out the porting, the fs crankcase is a lot smoother. the fs engines appear to have a more "finished" look to them.

[hoppy]

i must admit that is surprising... and interesting... once i get on top of a bunch of other work, i might well look into a zen/fs hybrid rebuild ;D

[speedyd]

just for shats and gaggles, idecided to put some fast eddys crankcase bearings in my old fs case along with some new seals.while it was apart i also installed a cy crankshaft,and did some minor match porting of the case/transfer ports.i also used some moto seal on each gasket to help seal every thing up real nice. ive got the "longblock together, but i am missing some pieces like the flywheel and clutch housing. so i am going to have to pick these up. i also am planning on an 813 carb as well.(i run them on all my cars). im not sure what im going to put this thing on yet but it is built, and i am curios to see what these little mods did for it. the cy crank is quite a bit lighter than the fs so i should gain some rpm.

[hoppy]

this does sound very interesting! :-D

[speedyd]

yeah, now i just need a chassis to put it in! its coming though.

[speedyd]

it was just on the bench, but today my modified fs motor came to life.it sounded like it has much better throttle response.now i just got to get my chassis in race form.