Serval Cat

[Snopczynski]

I understand how a 2 stroke pipe works, not claiming to be an expert pipe builder but it is a important part of building a motor, no need to explain. The characteristics of a PC or any other low-mid pipe in there inherit nature of design IMO, will never be the pipe of choice for this motor. If you think that you can make another 10 peak hp out of this cylinder by using a low-mid setup then i guess I fail to understand your logic. You say your looking a motor that is basically a tractor but you come back with "I know the motor can make 90+ hp with pro circuits, mid tension reeds, and 30mm carbs"??? I hope that there is better setup and i guess im a little confused at what you are looking for. You said that you did it with a 7mm cub, lets see that graph and let me compare it to one our cubs. I honestly dont want to compare your dyno graph to the serval that we built because its comparing to different breeds to each other which would not be fair for you. I know that you think your logic is the best possible setup, and it may be, but until you can test it lets lets leave it at that, "theory". I hope this continues to grow as a discussion and not an argument because i do not want to steer away from the good of the thread.

 

Have you ever ridden a big motor. I can assure you that i can show you a bigger motor that will make more power from top to bottom than any stock stroke stock cylinder that you have ridden. Maybe that would be something for you to consider. The problem with a motor like that is who wants 120+ hp in the tight trails, maybe you, but for the most it would be too much.

The things thats making this hard to convey is, pipes have to match durations for the motor to work the "most" effectively. So far no one has matched a pipe to the durations of this motor properly in my opinion. So they have not seen the maximum power the motor can create at its given peak rpm. They also haven't seen the max power it can create up to that rpm. Just because you put a pipe on the bike that works to 9,500 rpm, doesn't mean the pipe will improve everything in its range up the 8800 rpm (better than a 8,800 rpm pipe would) or so that this motor will want to rev to with the durations it has. A pipe that is designed to peak at 8,800rpm instead of 9,500rpm will make more hp in its working range because they are typically designed to work sooner, and the cost of working sooner, is cutting the peak rpm of the pipe shorter. Your not utilizing the power like you could be. I guess another analogy for it would be:

 

You have a glass of coca cola (serval cat). You have a straw (pro circuits), and you have a 1.5" piece of pvc pipe (cpi's, shearers, T5's). Are you gonna drink the glass of cola with the straw or a 1.5" piece of pvc pipe?

 

I have ridden that re-sleeved cub on some sand trails, in some idiot holes, and I have drag raced it for fun out on the strip in Coos bay on a holiday weekend.

[AKheathen]

Well only testing will see. I still agree that there is power left on the table as i know that i will be able to improve on this setup. I will however agree to disagree that the pc will ever be a pipe of choice on this motor as i just do not see that small of a pipe ever being able to keep up with a cylinder that flows as well as this one does. I hope that I am proven wrong as my ultimate goal is to improve the sport and offer the best combination available.

 

I will try and get it back on the dyno in the near future for some more test. If your interested in getting a setup together shoot me a pm and we will set you up.

i need to, well, rather compelled to, disclaim..........I'M KINDA DRUNK.........

that being said, i need to stop you right there and press the point that pro-circuits can be real hungry pipes, that only truly open their potential at the 4mill level. un-ported, they even fall short of sufficient flow to really shine, or wake up and stomp t-6's. their very design is based to compliment the high flow rate- mid timed mx porting. although the several's are timed slightly higher than what i feel is ideal, or perfect matched, the do fall well within the range of the pipe. (for the record, i favor the idea of 183/124 area to broaden the low-end of p/c's into an un-believable monster)

ok, i just have to say, that i really wish i could spare the funds right now to trial these cylinders on my 4mills. i just about have the perfect set-up and conditions to give her a good go for it. 30mm lectrons, boysen power, and pro (whatever i feel for the ride) dd lock-up, etc...multi- terrain ridding, and so-on...... jeff may thin he is a loner on this, but i, too am an advocate to the low-end, though not-so-stuck. what he is trying to press, imho, is about the same thing i was trying to convey months ago. torque is the big thing. without it, you do not have hp. hp, is merely torque x rpm (the twisting force in time)= amount of work measured in "hp", or "power" it's just marketing, and hearsay, that "power" is conveyed as terms of comparison....much like the water-electricity parody spawns mis-conceptions about current. so, you have (i.e.) 45ft/lbs at 6500rpm and get like 80hp, but the other guy has 90hp @ 9200, but only 35 ft-lbs......in a controlled environment, like drag, he may be ideal for getting there, but when you step out into the real world, you can get near 6500rpm a lot easier and quicker than the guy trying to work the shit out of his bike to get some power, since another by-product is off- power drivability, which really suffers the more extreme you go on the build........ok, i'm loosin my thought process........

i do see what these cylinders are made for, and how they were designed, but i cannot agree that they are low-mid cylinders, that would shine best on the dyno via low-mid pipes. i can see that they would be most fun, and usable, not to mention the likelihood of awe-inspiring out-put that pro-circuits can stretch these to, imo...it is my understanding, that the cylinders make the power, and different pipes are just differently tuned turbos...in relativity (i know there is much more than that to it) and that is the attitude i keep in my head when matching things. so, when looking at a build, i first pick the pipes to suit the needs, and set the motor in that range, usually not perfectly matched, but within range, non the less.....so, one key with these cylinders i see is, the flow. it cannot be ignored. i did not see mentioned, but i would also like to see these in action on a set of rockets, and every DECENT flowing pipe from mid-high on down. i do- have to reiterate, that pc's may just be a choice pipe for these cylinders......maybe not thee choice for most in love with top-end pull on a drivable motor, but likely out-shine the credit you are currently viewing the combo.

[bode1]

Anyone have an extra set of PC's they could send to Andy?

[No Limit Powersports]

The operating range of these or any other cylinders are not soley reliant on durations. Something I was once totally hung up on myself. It does not take a high port timing to get a motor to rev or make peak power at a higher rpm. With triple transfers and triple exhaust it takes less port time to get a motor to rev. Tradition has it most stock non tripple ported cylinders will rev better with a high port timing 200+ but I have found after many discussions with Calvin and many different port layouts that high ports are not always better reving ports.

 

Yes on my dyno this motor peaked a little lower than I expected it to but with more load on the motor I'm sure it will peak higher. The operating range with this cylinder is very broad and the motor will make power over 10k rpm. Which is where I feel the pc will fall short. We always build a motor to suit and pipe to the motor.

 

I think nate told me his made power over 11k but still came on at 3500-4500 which is basically off idle for a two stroke. I will gladly test a set of pc if someone has some.

[AKheathen]

i first have to apologize for my ramblings....i was actually really drunk, lol.......i cannot agree with you more on the port time/area. a subject i completely forgot, once i started typing last night. i really would send you my pipes, but i'm kinda using them right now, and the shipping both ways would cost as much as a useable set of used pipes down there....and, i would have to go back to the white pipes (origional gold series) i honestly don't think they will hinder at the 10k level as much as most think. they do rev broadly past 9k range, not so abrupt as most, which is one of the things i love....i can keep the r's climbing in a high-speed power slide and not have to change gears to get back down in the power. on a side note, these are pretty close to what i was considering having made in pv version. you say that 3500-4500rpm is basically off-idle for a 2 stroke, which is about right for a banshee, in perspective, but i know a 2-stroke can do better. my long-term goal is to build a pv'd engine that actually responds off-idle, but really runs like a 2-stroke twin. i wonder if it's plausible to run these cylinders strait-piped with stingers to see the real nature of the beast.....

[Snopczynski]

I cant stress enough that I dont want someone to just test a set of pc's. I would like to see smaller carbs, low-mid reeds, and pc's tested on it at the same time. I would also like to see timing in the +4 to +5 range with some more compression. Im looking for someone to test a full low-mid package on it. We can't do pc's with 35mm carbs, and vforce reeds. That would suck.

 

No spare pc's here right now, we are using all 6 sets we have right now on the bikes. If anything gets torn apart I can look into it, but everything is running good right now.

 

I got a hold of one the dyno sheets for one of the re-sleeved cubs set up for low-mid. It made 58.78 ft/lbs of torque and 93.96hp with a 7 mill crank. It has 1,500 rpm of torque backup.

[Forcefed]

Being as certain as you are about your proposed setup (which very well may a good one) IMO - Pulling a set of pipes off a bike for a quick test would take less time than all the keyboard time spent so far.

 

But even then ... comparing dyno #'s from diff dyno's is like ... well we all know what that's like.

 

We have had a couple reply's from real world riding that seem to make these cylinders a pretty darn fun bike to ride.

[Snopczynski]

Being as certain as you are about your proposed setup (which very well may a good one) IMO - Pulling a set of pipes off a bike for a quick test would take less time than all the keyboard time spent so far.

 

But even then ... comparing dyno #'s from diff dyno's is like ... well we all know what that's like.

 

We have had a couple reply's from real world riding that seem to make these cylinders a pretty darn fun bike to ride.

Even if I come up with the pipes, people need to come up with the carbs, domes, and reeds. My pipes just got ceramic coated, and I just got my bike put together for a ride in 2 weeks. So my pipes arent going anywhere but the Oregon coast.

[Forcefed]

Couldn't agree more !

[Snopczynski]

I sent Andy a pm about getting one.

[RobertR]

Ive got 28mm carbs, stock reeds and a set of Paul tuners on stock cly with .40 over and it is a low to mid motor.I would love to do some testing but I have also seen them in action and was impressed with then at the set up they were running.

[Phelps]

man i hope ppl didn't want want want when the cubs came out. i blindly purchased a set before Calvin was ready to release them. it was basically a "pay me to send you a set asap and we will call with any dome, port etc improvements as we receive them" Nmotions called me i bet 4 times with different combo's making different numbers for 6 months. just to bad back then i couldn't afford to make the changes, but never the less i could have not been more happy with my spending's.

 

i can't believe you guys are so reluctant to buy a set and try them yourself. ppl swap parts here all the time and surely you could find a setup that is "perfect for you" after my first encounter with calvins products i could honestly say that if i had the cash i would order a set from Andy today.

[AKheathen]

i would also love to put them to the test on the wild alaskan "course", lol......i think he is too far past r&d hand-outs/trials....and i have the full low-mid setup, too....lectron 30's w/pj's, boysens, dyna fs programmable, dd lock-up, billet basket, 22/12/9 mud tires, ptr powerhead, pcp's, etc, etc...enough to handle the abuse, and even spare pipes/reeds, etc to change things up a bit....i'm just on the fence about shelling out for the cyls, or continue with what i was buiding up already....

[Snopczynski]

The way I look at the swap is not just putting in a 4mm crank and the serval cylinders. I am gonna need a hinson basket and possibly will want to do a lockup also.

 

Also, right now my bike runs good, and has nothing wrong with it.

[okbeast]

I've kinda wondered if this hp/tq range is getting into the lockup range.

 

But I am one of the few that has had a bike with a lockup and 85+ hp and it shift fine without an override. No it wasn't perfect for drag racing but was very rideable.