125cc Mod Engine

[machinedcomp]

What ever became of the 125cc Kart engine that was going to be used in the Mod category.

[johnsonm50]

I remember seeing 1 or 2 run experimentally from patrol boat at Lock Haven, Last I heard of them.

[DeanFHobart]

What ever became of the 125cc Kart engine that was going to be used in the Mod category.

I heard that Howard Pickerell was working on this.

[Fastjack]

he had one running very well @ Thompson Ct. Rossi lower = electric start=tuned pipe.

[Flatiron]

I was very interested in these myself. I would like to do some tinker with one. As a new guy I think supply and demand for the Yamato is a freaking joke.

[pav225]

Order a new 321. You can have it delivered to your door within a few weeks.

[DeanFHobart]

he had one running very well @ Thompson Ct. Rossi lower = electric start=tuned pipe.

Do you know the speed or any other performance features? What is the cost for the Rossi unit and power head?

There are several brands of power heads available, is that correct?

[Bob Rusnak]

I did see the engines at Lock Haven, there were two of them there. I think there is a potential for these as the power heads are available and pro units of several different types are also available. The ones I saw were running on gas. If converted to alcohol they just might be able to run in the 125 pro class. Like the electric start.

[ddalton]

Not a chance, 28hp,3port motor.low comp.Ment to be a Spec. Class.Perfect unit to bridge the gap between K-Pro and 125 class. But if someone wanted to put a proper chamber on one and up the comp,bigger carb,etc.could be 125 jr. in Title Series. l showed one at Johnston City race in Sept.

[Hydro doc]

What do you think the motor would weigh?

[j hydro racer]

While testing at Lock Haven, I was asked to jump in one of the rigs. Think its a great project and Howie has been working hard on it. If we put this motor on a boat the size of a ash, I think it will be a great class for younger/ smaller drivers who want to race mod.

[chuck w]

That was my boat. Hope you enjoyed the ride

[DeanFHobart]

So, they are running in the 55 mph range, + or -?

[j hydro racer]

Didnt have a gps on but probably around 55-57.

[Dr. Thunder]

So how would you convert powerhead from gas to alcohol or vice versa? Do you have to use kart engine or could you use a Rossi or GRM powerhead?

[DeanFHobart]

So how would you convert powerhead from gas to alcohol or vice versa? Do you have to use kart engine or could you use a Rossi or GRM powerhead?

I don’t think you would want to convert one of these ‘gas’ go kart power heads to Methanol. The crankshaft and rods would not be strong enough. The specifically designed methanol engines like the Rossi or VRP are the way to go. The Rossi and VRP 125 engines are getting over 50 HP I understand. I’m not sure of the horsepower of these go kart engines, but I would think they are not close to 50 HP.

Does anyone know the HP of these go kart engines?

Of course, unless you are a person who just likes to tinker and wants a challenge. Just keeping any racing motor running properly is enough of a challenge in my opinion.

[ddalton]

Tested this one in Canada in November 2016. on a Pickerell B Hydro and seen just shy of 61 mph. Didn't get near it this year, But with renewed interest in the class will get back to it in 2018.Rossi tower and Konny 11:17.Should see 65mph with smaller/lighter hull...

[csh12M]

ddalton - can you message me your phone number? I would like to discuss this with you. It looks great, love the way you mounted it and would like to learn more.

Thanks,
Dean

[DeanFHobart]

Tested this one in Canada in November 2016. on a Pickerell B Hydro and seen just shy of 61 mph. Didn't get near it this year, But with renewed interest in the class will get back to it in 2018.Rossi tower and Konny 11:17.Should see 65mph with smaller/lighter hull...

Very cool.... Keep us informed. What is the estimated cost of a unit like this?

Thanks.

[bmitch1]

As I understand it the Mod Commission is currently reviewing specifications for the class, hopefully in preparation for running the new class in 2018. Information should be forthcoming from the New Class Committee and the Mod Commission by the National Meeting. I commend Mr Pickerel and his associates for the development of this motor - combining a mass manufactured racing powerhead with a customer choice of towers on the reliable gearfoot. I've been following the development of this motor throughout the summer with great interest and here's what I can add to the information...

The PRD Fireball is a karting engine developed for "TAG" racing (aka: Touch And Go") in the kart classes - in karting this is similar to our 300ssh class in that they produced a reliable water-cooled, electric-start powerhead to attract entry-level kart racers. Based on information from karting vendors the powerhead alone can be purchased new for around $1250 US, or as a complete powerhead package containing the powerhead, starting battery, exhaust header and pipe etc for $1,750. A complete racing outboard motor will also need an powerhead-tower adapter plate (being reviewed for production - cost TBD), a tower (more on that below), and the gearfoot. A complete motor would probably be something less than $3k (Note these are my calculations only... so I'll include a disclaimer: No representation or warranty, express or implied, with respect to the completeness, accuracy, fitness for a particular purpose, or utility of these materials or any information or opinion contained herein. Actual mileage may vary. Contents may settle during shipment. No user-serviceable parts inside. Use only as directed. Freshest if eaten before date on carton. Subject to change without notice.)

Specs on the PRD Fireball (copied from a karting supply) are:

• Type: 2 Stroke water cooled single cylinder reed valve induction
• Capacity: 124cc
• Bore: 53.6mm First Piston
• Stroke: 54mm
• H.P. /RPM: 26HP / 15,100 RPM
• Carburetor: Tillotsen HL-360A or HL-166B (spec IKF)
• Ignition:C.D.I. (Oppama)
• Ignition Timing: 2.20mm BTDC
• Spark Plug: Denso W27TU (Run in only) W29ES-ZU (recommended racing)
• Fuel Oil Ration: 20:1 Premium unleaded
• Piston Type: Uncoated Single Ring
• Piston Clearance: 0.10mm
• Ring Type/Gap: Flat 1mm thick/0.25mm
• Cylinder Head Volume: 11.2cc
• Compression Ratio: 7.5:1 (nominal)
• Crankshaft: 2 piece, forged & induction hardened, fully ground
• Conrod: 100mm steel forged & machined top and bottom needle roller bearing

We raced against this motor at Lock Haven using our 200MH and it was definitely running north of 57 and seemed capable of more. I've been told they expect to see low/mid 60's once racers have a chance to test some props and work on setups. For that reason an A-boat will probably be a little small for the expected speed, and the consensus seems to be around a B-size rig. Due to the dyno curves on this motor the props are pretty small by comparison to other classes.

The development team is also reported to be working on options to allow the use of various towers - allowing racers to mount the motor and gearfoot to a variety of readily available midsections - including the 15 OMC, Rossi, mod-style Yamato's and I'd guess even 15 Mercs. The adapter plate that the development team is working on is an engineering marvel given that the karting powerhead was originally designed for a road-going use, and has now been mounted sideways on an outboard tower.

[DeanFHobart]

Very cool and congratulations to the development team. I am looking forward to further information on this class.

Technical Question: Is it difficult to keep the engine on the pipe or is the port timing such that it stays on the pipe easily?

Also, is the Commission looking at making this a ‘Sealed’ engine class... with the possibility of a single propeller like the 300SS Hydro class?

Thank you and again Congratulations.