70 TCCD porting

Anyone ported one of these? Tips on where a lil more power can be squeezed out of it?

Re: 70 TCCD porting

dont be a pussy james.

bottle of jack, dremel, and a little bit of good old fashioned american go getternessism.

Re: 70 TCCD porting

You can really fuck up a good cylinder with a bad port job. Don't just start hacking away at the ports without any idea as to what you are trying to do. Get the timings on the ports, run some math, read up on all the two stroke tuners books you can find and figure out the best port timings for your pipe of choice. Make some aluminum spacer gaskets to raise the transfer ports to the specific transfer duration you calculated and make sure all the numbers work together (i.e. time it with a measurement wheel attached to the crankshaft) and then fucking rip.

Re: 70 TCCD porting

or what finny said, i guess. i still like my idea better though because it involves both liquor and power tools.

dont worry finny, james knows his shit. or at least he knows better than to take anything i say seriously.

Re: 70 TCCD porting

i have modified the piston... they have different pistons... so if you dont have windows on top, or have 4 holes, make them into 2 squares matching the transfers on the top of the cylinder.

also, i was looking at mine yesterday, and i was thinking about opening the side ports a little on their bottom, and taking a bit off the sleeve of the cylinder too to match the inside of the ports

...if that makes sense.?

Re: 70 TCCD porting

just raise the intake and exhaust by 1mm. Widen the exhaust by 1mm on each side and widen the intake by like 2mm on each side.

then make sure its all smooth and rip.

Re: 70 TCCD porting

hmmm... the transfers above the intake are timed differently than the regular transfers. I think that you should make all the transfers open at the same time if you can get the dremel in there, or you could just dremel the top of the piston. Make the portmap look like this:

Re: 70 TCCD porting

The transfers above the intake are supposed to open about 3-6 degrees later than the main/ 5th ports. It is arranged this way to help push the air into more of a loop shape through the cylinder. I would suggest leaving the timing difference alone on that one.

Re: 70 TCCD porting

Yeah I'm not messing with the loop scavenging bit. That map looks pretty sweet, though; I'll probly give it a whirl.

Re: 70 TCCD porting

That makes sense. The portmap here will still work though.

Re: 70 TCCD porting

thats a pretty extreme port map. they have bad enough low end as it is. I've never ported one myself, but if I were, i'd do the exhaust in stages. I think its too big as it is for daily driving.

Re: 70 TCCD porting

My k star has great low end with just doing the two hole on the piston mod. And shining up the exhaust. If you take off the head and look at tdc, the piston already looks mighty low. I wouldn't suggest raising the jug. I'm gonna be doing the same porting that was mentioned a couple posts up when I get some bits for my dremel. also, I'm gonna experiment with a big carb and pipe. I know one of the ire dudes is running a 19. But with an estoril I'm pretty sure. It should be intersting how it reacts to a simonini.

Re: 70 TCCD porting

That port map is pretty much stock except for the exhaust port is more wide and maybe 1mm higher

Re: 70 TCCD porting

The K-star is quite a bit different. I have both k-star and TCCD. I just put the K-Star on with a 19mm carb and a modified Bullet pipe. I'll take it out tonight for a good run but I can say already that the K-Star does not have the same low end issues as the TCCD. Taiwan all the way babies!

Re: 70 TCCD porting

or try this:

take about 3 mm up on the intake side of the piston and make the holes into squares port the rest to the extreme shown.

made a k star rip but lost low end, use in conjunction with a well tuned 19phbg, and decent pipe that shitty kit will hit really high rpms

don't think too much, less math and more experimental cylinders will make ur port work better and u'll have more fun. just look at a puch low torque cylinder there arn't even port walls, try that on a kit i bet it rips.

also polish up the exhaust.

Re: 70 TCCD porting

duders, do exactly what elliot did.

Match with 21 dell and a modded clutch and you will rip balls.

My kstar ported with a 19 dell, stock gearing, and biturbo has nice low end and hits about 45 no prob, with a simo it goes just about 50 and great low end.

Then i also had it with a proma circuit and dear god. I was keeping up with zach lee's blaster puegeot on a hill race battle.

Re: 70 TCCD porting

Never worry about low-end when porting, unless you want to ride with a stock clutch.New top-end power is always taken out of the low-end power.

The portmap that Eric posted is very conservative compared to my portmap. Elliot's portmap looks a lot like mine, altho I didn't raise the intake like he did, I just widened it and shortened the piston.

My TCCD gets a good 45MPH, but that's because I gear low. I'm not a top-speed guy, I am however a high-rev cylinder guy. My kit screams (11.5k RPM) and absolutely rips with both a Proma Circuit and a Proma LowBoy (More top-end revs than the circuit).

And as a final tip: Always bring the exhaustport to 67% of the true bore, as it will give you maximum torque with minimum piston(ring)wear.

Re: 70 TCCD porting

Roald, just wondering what sprockets you are using?

Re: 70 TCCD porting

Would you happen to know the port durations that you cut your kit to? And perhaps compression as well? And maybe ignition timing too if you don't mind giving away all your secrets. Thanks in advance.

Re: 70 TCCD porting

i might have exaggerated the ports a bit (its just a line drawing) but u get the idea, go for broke or go home.

sry no other specs for this kit, maybe Roald has some more info for ya'll

Re: 70 TCCD porting

@Jesse:

I don't mind giving away the full monty, I don't really have secrets.

I don't have a port-map ATM. I always seem to throw them out, altho I always think: I'm going to keep this map for later referrence... I'll make you one when I have the time (My bike is in parts ATM anyway).

I've never measured compression. My way of checking compression is as follows: Turning the flywheel should be so hard to do that it's impossible to check for spark by hand with the sparkplug in and when you start the bike you need to have your full weight on the seat. That's when I'm satisfied about my compression. Maybe I should measure, as a real compression tester is about 15 bucks or so.

Ignition timing... No clue, I don't do ignitions. I have a friend who is really good at getting it right, so I let him do it. Give me something electric to fix and it'll be on fire within 10 seconds. I do know it doesn't run proper with the key in.

Re: 70 TCCD porting

15-43 on the E-50, usually 15-45

15-36 on the ZA.

Re: 70 TCCD porting

I'd be very interested in the durations in degrees if you could, would make it easy to use it on similar kits. 11k with the circuit huh, what carb is that with?

Re: 70 TCCD porting

Yo, Justin, I'm starting to build up my swinger with the stuff you and tom brought me. Whered you top out with the proma circuit? I'm thinking about selling that simo and grabbing one, which one would you recommend?

Re: 70 TCCD porting

The circuit stops at around 10.5k, 11k if I got tailwind or going downhill. The lowboy gets it to 11k and 11.5k with tailwinds/downhill.

I use a 21mm Dell'orto PHBG with a foam TNT filter. 45mm HC head and Airsal piston.

I use the Airsal piston because my TCCD piston gave me issues with raising the cylinder enough to clear the head, it uncovered the intake through the piston windows at BDC losing a lot of power and fuel that way. The Airsal piston has the 4 lil holes model instead of the 2 bigger windows, and the holes sit a lil higher than the windows in the TCCD piston.

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