125 engines ... Pros and Cons ...

[Dave_E71]

If this multitasking female can drive one any of you can!!!

Kristi,

Does this mean if Chris can't come to Wilson you're going to multitask into his 250?

BTW My offer still stands, you can be my other crash test dummy....

Dave

[mercguy]

well.....................175H

Come on Darren, that is not even to race one, we are just talking the basics.

Plus for that little effort, you get a great ride, no tear down at inspection and you know that the class will be around the following year.

Dr. Thunder, on occaision, as you leave the pits you may also want to make an arching turn to the left. Sometimes this helps bring the rev's up enough to get the boat on plane.

Should all of the above not work (which will be rare), you may have to resort to the classic Yamato Shuffle. Eric Pugh can best describe this elegant two-step made so popular by Yamato 250's and 350's in the early 80's. If you get dizzy easily do not try this!!

Of course, if you have a good prop (not too big) and a proprer set-up then your 125 should plane-off without too much effort.

if and when the 175H class picks ups/grows, I would actually like to pursue the class. I would even sell off all my 20SSH, CSR (or CSH, would have to make a choice) and Cmh stuff, keeping just a CSH (or CSR) rig and a DMH.....

[Joe J]

Daren:

I will order one from Litzell as soon as you do. Already have a boat hanging in the shop that would be perfect.

Joe

if and when the 175H class picks ups/grows, I would actually like to pursue the class. I would even sell off all my 20SSH, CSR (or CSH, would have to make a choice) and Cmh stuff, keeping just a CSH (or CSR) rig and a DMH.....

[epugh66]

I'm still alive. Thanks for the mention Dave.There's nothing quite like submarining a boat just to break the prop loose.
You can FEEL the pipe. Using either a hand puller or foot pedal, you can feel when the pipe falls off. A qiuck move up or down the range and BAM, you got power again.

[DougMc]

Very informative link.

[Andrew 4CE]

I was curious... as an outsider to the pro world... it would seem simple enough and inxepensive enough to make a servo controlled by electronics to match the length of the pipe with the rpm of the motor automatically...

Anyone doing this?

[hydroplay]

That's funny, Andrew, I've always thought the same thing too, especially back in the days when quite a few of the PRO guys used air cylinders to move the exhaust and they were either sort or long. A simple logic board with rpm and throttle position would be the only thing required to activate the air control valve. I always wondered why some electrical guy like Larry Latta never played with something like that. Nowdays there seems to be more modulation in sliding the pipes but a fairly simple map could be done based on some dyno tests. But then you still would have sensors, control box, activating mechanism and wires to worry about. Maybe the gains would be so slight that it isn't worth the added complexity and probably added weight. But then it seems in the smaller classes at least that the throttle is usually held wide open and engine speed controlled by the pipe. This would seem to require a fly-by-wire speed control system because you can't have the pipe trying to continually optimize itself when the driver wants to use it to control engine speed. Or would the throttle come back into play?

It seems that simplicity has won out for now but....

[Andrew 4CE]

Throttle wide open and slowing down by exhaust? Ah ok. Didn't realize things like that were done. Some model engines run like that. That would definately make it trickier.

Weight... I would think a servo for a 1/4 scale RC car could handle the back pressure. You might add 5 lbs? If you had a system you'd also remove the hand pipe adjuster and cables... so it wouldn't change the over all weight a lot and the major bonus would be freeing a guys mind for driving I'd think.

Anyway, was just curious. Thanks.

[David Weaver]

Electronic / Digital pipe pull

This is an interesting thought.

But there are the other principals of keeping it simple and having fewer "moving parts" to fail.

[Dan M]

Hydroplay,

Larry Latta did in fact have a system that he develpoed back in the early 80's. Did just what you said. Matched pipe position with rpm. Don't know why he abandoned it. He now uses a 12v linear actuator to pull his pipe. Has a switch mounted on the throttle for forward and back.

Dan

[Steve77t]

The best way with these NO TORQUE engines is by hand pulling the pipe. The good drivers know this and that is why they are successful at this. In Pro racing of all classes, because there are no weight limits, it comes down to a simple horsepower to weight ratio. The more you add in weight the slower the thing will get off the turn. I have been messing with 125's since 1975 and have learned along time ago, that it is easy to out trick yourself. So I use the KISS system, less to break, less to work on, better win slips. Rule of thumb in all racing . Tricks are for kids and rabbits. Racing is just good homework and studying. The reason a lot of guy's used air is because they could not move some of the multiple pipe engines or their hand was to small to pull the needed 5 inches that some motors used. None of this is real rocket sceince. I have said for years that if you race and are successful in 125, you will be the best 700 driver and anything else you get into. You drive a 125 and 700 exactly the same. If you do anything quickly to a 125, you blow the flame out. If you do anything to quick with a 700 you take very expensive parts out IE: Gearboxes, crankshafts, driveline stuff

[DougMc]

In Pro racing of all classes, because there are no weight limits, it comes down to a simple horsepower to weight ratio. The more you add in weight the slower the thing will get off the turn.

Steve,

So what is the most a 125 driver can weigh using a standard wood hydro, not a composit, and still be competitive in 125CCH? 150lbs, 200lbs, 220 lbs?

[Steve77t]

Boy1 What are you trying to do here? get me hung by a short rope? Without the 125 guy's comming at me with pitchforks and such for guessing wrong, and me not ever working at a county fair, Id'd have to guess at the lightest being around 125lbs and the most heavy at around 190. Where the parity comes is the heavy guy's think and watch the onces as the pounds then fall so to speak.

[epugh66]

None of this is real rocket sceince. I have said for years that if you race and are successful in 125, you will be the best 700 driver and anything else you get into.

There you go boys and girls, the best summation and quote you'll read for awhile. Go a head and print up some shirts.

A look at the results books will show this. Stevens, Hellsten, Pugh, Nydahl, Eldredge, Latta, Kugler et al.

[epugh66]

The reason a lot of guy's used air is because they could not move some of the multiple pipe engines or their hand was to small to pull the needed 5 inches that some motors used.

Also, the air systems helped a Lakeland. It was a little tricky to use your right hand to reach over and put the block of wood or loop of rope over throttle/pipe puller combo. After three laps our hands got weak...girly 125 drivers.