125 engines ... Pros and Cons ...

[Dr. Thunder]

I'd like to get more perspective on the various pros and cons related to current 125 engines ... Rossi, VRP etc. Who is running what, why, what are the strong vs weak arguments for or against each if any including economics to buy, maintain etc.. So, if any of you Pro guys want to help out a newbie with this subject it would be appreciated.

[RONUS]

Try also...

You can also check at www.boatracingfacts.com there may be a few more pro guys that can answer your questions. Try also looking up David Weaver, he seems to know quite a bit about the 125's

[RONUS]

????

I'd love to help you out, but I've been away from this stuff too long now.

Dave

[STEVE FRENCH]

Give Graig Dewald a call. He has a 125 that Billy Allan pilots. Plus he can supply ya with a winning wheel/prop...

1-610-926-2964

19P

[Steve77t]

Both motors that you ask about are competitive in 125 hydro or runabout. Ther seems to be about equal numbers of both types which makes the win for my brand much sweeter. Like any motor for racing wheather for stock mod or pro good care is important for consistant performance. as far a toughness goes I havent heard of any problems with any of the 125 motors with crankshafts or other major parts. Like any high breed motor and as mechanics tune to maximum output an occasinal burn of the piston results. This is usally repaired in about 15 minutes.I invite any that knows nothing about pro motors to please ask the guy's in the know as there are many false statments about PRO racing and motors.
Steve

[Mike Schmidt]

125 motors

There are only two choices in 125. VRP and Rossi. Both very similar in performance, cost and design. In 2004 a Rossi won 125 hydro at Depue, in 2005 a VRP won. At Lockhaven this year we had a great 125 race. Had a early Rossi (short stroke) a late Rossi and a VRP. Each one won a heat...

We have both a Rossi and a VRP 125. In back to back testing the VRP is a bit faster around the race course. The Rossi has not been carved on like my 250's yet....

I do a lot of motor work on the Rossi's and VRP's. I feel that the design of the Rossi makes it easier to work on, if your going to try to improve the performance of the motor. The Rossi takes it design from the Yamaha road racers and uses a lot of parts ( rods, bearings and seals) from Yamaha. The VRP is Honda based and shares similar parts.

The Rossi is a complete motor. Comes in a wood crate. Comes with throttle, throttle cable, pipe puller cable, motor mounts and thrust bracket. My 16 year old son assembled the won that won Depue one in in about an hour. The VRP is more of a kit motor. A very nice powerhead and exhaust, but you have to supply most everything else. There has been talk about VRP producing gearboxs this year. 11:15, 12:16 or 11:17 are the only gear ratios to run.

Call Craig about props. (610-926-2964) Craig has a 125 Rossi that runs in the hydro and runabout class. They test it like a stock motor (a LOT of testing) His two drivers are new to PRO and are the three of them are still learning. This motor has had the dog snot beat out of it and it just keeps running. They are great little motors.

I bought a new Rossi 250 a couple of years ago. Ran it 25 heats of racing that year. Started first pull 25 times. Won 22 heats of racing, came second three times. At mid season I changed spark plugs, because I felt I had to do something to the motor....The modern Italian PRO motor is a very dependable motor.

Steve Litzel imports the VRP. Rex Hall imports the Rossi. Both are the the USTS races with parts and tuning advice. The choice is kinda like do you buy a Ford or a Chevy...

Michael D-1

[David Weaver]

125 Engines

I believe that Steve and Mike have covered the topic well (and in an impartial manner). Steve metnioned to me that lower units from VRP are on the way for evaluation. I am not completely sure, but I believe that you can get a factory tower and pipe bracket from VRP now.

Like Mike said, it is kind of like Ford or Chevy, but the competitors get along better and hopefully they are not down sizing.

I will mention that a Mac Minarelli was in position to win the 125 national championships last season until Bruce Summers had an unfortunate collision with a turn bouy in the final heat. Mac's are out of production however. Arens from Germany offers a 125 engine, but I have not seen any imported.

Either way, 125 is a great class. Affordable, dependable, increasing in numbers on entries, etc. Also, the 175cc hydro class is offical in 2006. Both Rossi and VRP have engine available. The VRP is a 2 cylinder and it is just neat a little engine that can get you to 80MPH very easily, but without a lot engine weight or heavy tourque. The US will host the 175cc World Championships in 2006 and has put in a bid for 2007 also.

[Fast Jack]

125

I am in the process of puting togather a 125 Rosi / Oconner package for this season. I went to a USTS race with Mike , Dave Jones had his 125 also. I learned a lot walking around and talking to the racers. This a move up from CMH for me. The 125 came in a wooden crate from Rex Hall, it is very complete,and very high quality. Everything has gone togather very well so far , Looking forward to going to Fl , going to run Inverness and stick around and run Avon Park the next weekend. The tower can be set up so you can run both powerheads ( Rossi/ VRP ) ( not at the same time!!!!). Ill let you know how things go .. Now how to get that 55 gal drum of alky into the shed.

[Dr. Thunder]

Gear ratios ...

What can you tell me about the various gear ratios that are available? Why is one preferable over another ... under what conditions, cir***stances would you use 11:15, 11:17, 12:16 etc. With regards to carburetion ... which is the preferred carb and why ... what about jetting ...

You guys have been great so far ... thanks

[David Weaver]

Additional 125 Questions

I believe that most 125 hydro drivers are using 11:15 or 12:16 gear ratio's. Good combination of acceleration and top end. The 11:17 provides more acceleration, but may give a little on the top end. The choice of 11:15 or 12:16 may depend on one's preference for the Yamato style versus the Konig style case.

Both the the VRP and Rossi come with a carb. Typically the Rossi has a Delardo and the VRP a Mikuni. Both seem to work well. Jetting takes a little practice and is important to pay attention to the engine's performance when testing on race day. The majority of engine problems in 125 hydro (and 250 and 350) is running the jetting to lean. Plenty of specific advice is available from Rex or Steve with your purchase!

DW

[Tim Brinkman]

125 Vrp

If you are looking to buy one we still have the 125 VRP that won the 2003 hydro World Championship and the 2004 runabout National Championship for sale.

[Dr. Thunder]

Thanks Tim ... sent you an email.

[Andrew 4CE]

what are some realistic speeds that 125's are hitting on the race course?

Hydro and runabout.

[Mike Schmidt]

speeds...

On the hydro, mid to upper 70's. There is talk about 80 + mph 125's, but I have not seen them yet. The boats are a lot like a C mod boat. Don't have a clue about runabouts.

Michael D-1

[David Weaver]

80 MPH Plus?

There is talk about 80 + mph 125's, but I have not seen them yet. The boats are a lot like a C mod boat.

Michael D-1

Come down to Georgia!!

I know of one or two that have seen 80 or better testing, but the set-ups woud not have worked well in competition, unless it had been a 1 2/3 mile course. One of these was a VRP right out of the box. These were GPS readings on different occaisions.