- Location
- Buffalo, NY
Please keep us updated when you do. Thank you.
Damn really. another cylinder for angry people to attack people on
- Thread starter waxhead
- Start date
Please keep us updated when you do. Thank you.
waxhead
wannabe backflipper
- Location
- gold coast
We will do. We are doing an intake manifold and will be releasing a cylinder head for the Yamaha as well with modern style domes not the old leaded domes that every one sells
- Location
- Buffalo, NY
That's excellent news! Looking forward to seeing all these great new products.
- Location
- the jetski grave yard
Cooking up Looks like it needs a hefty dose of sauce/spice to me. Stock stroke 700cc is going to be a under powered turd no matter if it has gas valves or not. Who's already manufactured cylinder are you going to copy/knock off? Did you ever finish your Coffman half pipe knock off copy? is that still cooking or on the back burner? Haha
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
Really? Got nothing nice to say, don't say it...
Big Kahuna
Administrator
- Location
- Tuscaloosa, AL
One person just got a temporary ban... keep it up
Vumad
Super Hero, with a cape!
- Location
- St. Pete, FL
I'm not saying I will front the money, but A cylinder with powervalves that doesn't require case modification, a bolt on cylinder, is what I would be interested in. I have ridden stock motors with porting and I do not like them. I am very pleased with my stock cylinder porting that is very smooth, consistent and linear like a 4-stroke bike. The ported motors I have ridden make more power are very pipe-y like 2-stroke dirt bikes and I do not like them. I not only prefer that smooth power but I do just take my superjet for a cruise at lower speeds and a ski that jumps on and off pipe just is not the right ski for me.
I have ridden a XS900SS setup for racing and it was a ton of power that was super linear and smooth. I think that I would be very happy to rebuild my motor with an affordable stockish displacement with a powervalve setup. Again not saying I am a customer as I am very price sensitive but I have always thought there would be a good market for a cylinder like this. Most of the top end kits I have seen are in a price range I would consider but when adding in the case and other modifications it quickly became unaffordable for me.
I have ridden a XS900SS setup for racing and it was a ton of power that was super linear and smooth. I think that I would be very happy to rebuild my motor with an affordable stockish displacement with a powervalve setup. Again not saying I am a customer as I am very price sensitive but I have always thought there would be a good market for a cylinder like this. Most of the top end kits I have seen are in a price range I would consider but when adding in the case and other modifications it quickly became unaffordable for me.
- Location
- the jetski grave yard
I don't pat people on the back for doing nothing but I do agree with the title that could use another few descriptive words in there
waxhead
wannabe backflipper
- Location
- gold coast
We are not looking to make a flat water back flip engine but a good strong surf engine and general hack around engine. When you think about the development of the two stroke over the years you realize that there is more to it than just capacity. Will the 701 pull a 160mm pump to a standing flatwater back flip ? NO it not the market we are after. That's for tpe and all the other engines out there
- Location
- Florida
Love the development and tome y’all have put into our small hobby! You guys rock!
- Location
- the jetski grave yard
So cast pistons are now better than forged pistons? Wow , I wonder why high performance race car engines haven't been running cast pistons all these years. I guess my certified, licensed master mechanic training and experience is all just smoke.
waxhead
wannabe backflipper
- Location
- gold coast
When they were dyno testing with the two stroke gp bikes they found a power increase on cast pistons over forged pistons. Forged pistons can handle deto better but the cast made more power on the dyno.
This was straight from Jan Theil and Frits overmars who were responsible for the 54hp 125 rsa Aprilia engine. Im probably going to listen to what he says as he has the runs on the board. There is numerous links to this but here is just one of them
[GP125] All that you wanted to know on Aprilia RSA 125, and more, by Mr Jan Thiel and Mr Frits Overmars (PART 2) (Locked) - Page 14
Howard Gifford a écrit: My thought is to give the port a slight taper starting at 34mm at the carb tapering out to 36mm at the plate and ending at 38mm where i
Transfer Theory by Frits Overmars aka The leaning tower of Pisa
2 stroke racing minimoto motorcycle racing 125 GP NSR50 fabrication MotoGP
bucketracing.blogspot.com
- Location
- Western NY
forged pistons are stronger but that also means harder and also they have a higher CTE, cast pistons are weaker but have a lower CTE. In a naturally aspirated two stroke, where piston strength isn't really the main concern I agree with wax that the cast piston that lets you run a tighter clearance because of lower CTE is the better choice. Especially on a plated cylinder where you really don't want a harder piston slapping around in the bore until it warms up. On a high boost 4 stroke engine where piston strength actually becomes a concern, clearly a stronger forged piston is the better choice. In that application your max piston temp is also higher, causing you to run increased clearance in the first place so they will be slapping around until hot whether cast or forged. Or atleast that's my take on the matter
No, but you'll p*ss on their lawn for trying something. That's bk's point
- Location
- Spring Lake, MI
Have you compared your porting for this cylinder to a jm big bore? I know the powervalves are a game changer for the smaller bores but I'm curious what I could expect doing a direct swap from my 200psi, dual 44, zeel, bpipe jm771.
waxhead
wannabe backflipper
- Location
- gold coast
We are looing at a triple exhaust port. this gives a much better blowdown t/a. which means then you can run a lower exhaust, Longer power stroke. I have not held a jetmanic ported cylinder in my hand and so I cant comment. At this stage im still considering if to run the power valves in it. Im looking for a low stress bolt on power adder
WFO Speedracer
A lifetime ban is like a lifetime warranty !
- Location
- Alabama
What kind of HP numbers are you looking at with this cylinder, I know most PV engines have really good HP numbers Seadoo 787 110 HP, Seadoo 951 130HP, Yamaha 800 125 HP, Yamaha 1200 155 HP
waxhead
wannabe backflipper
- Location
- gold coast
I really haven’t been looking at power figures just yet I’m just looking at designing a better cylinder than what is out there for the guys who want an upgrade on a stock stroke crank. I would not even want to suggest what power it may make and thus open myself to getting slammed because of a gotcha moment. Most of the engines you have talked about there make great power but there is a lot more than just a power valve adding that power figure.