Hi Guys,

Lots of good questions here, and here are my thoughts:

First I think there will be many competitive sleds that fall under the 440 cc / 1981 rule. There are the consumer versions of the 78-80 SRX, Ski-Doo RV's and Blizzards, Polaris TX's and TXL's, Rupp Liquid Nitro's, Cat 78-79 440 LX ElTigre's and the 79 CC ElTigre, not to mention the 76-77 Cross Country Cats, Kawi Invaders, Intruders, ect.

I think its going to come down to set up, preparation, driver skill and fitness more that the make of sled.

As for the Liquifire motors, I really don't like the idea of removing the oil injection from the 80 LF. First thing is that the water pump is driven off the oil pump, so cutting off the oil supply it doesn't sound good to me. Secondly, the chrome bore is more the problem with gas washing the oil off the cylinder at the intake port. Note the a fair amount of oil already enters at the intake port. I also like the oil entering the center bearing location, unlike the Trail and Sportfire set up where oil only comes in at the intake ports.

The chrome bore is a materials issue, as oil does not adhear to chrome like it does to iron or nicasil. The fix I intend to go with on my Liquifire is getting my cylinders nick'ed and running new WISCO piston with chrome rings. Nicasil holds oil better then chrome, is a thin coating so it will transfer heat well, but it will wear out the stock type iron ring.

General rule of thumb is chrome bore - iron ring. Iron or Nicasil bore - chrome rings.

More to come...

-Rainville

As for Mitch's question about 78 Liquifire's, I think he has a point.

Some guys just like the bigger chassis Deeres from 76-78. I ran my 78 CC in the first vintage challenge, and really enjoyed the ride, but that sled has a rubber track and an 80 Liquifire like rear skid. Again with proper set up I would think a 78 Liquifire or Cyclone 440 could run well. The LF only had 57 hp in 78, where the 80 was about 65. But I perfer the case reed motor for mid-range and iron bores for longevity. The 78 LF also has a radiator the 76-77 sleds don't have.

I generally agree with Ted that he 76-77 Liqufire's with the steel rear skid and cleated tracks wouldn't be my first choice unless updates were allowed. I don't mind trail riding one, but racing is another story. To be honest, I really thought about putting a 440 top end on one of my 78 CC's, but decided that the 80 LF is very plentiful with about 9,000 built, parts are pretty easy to find, they are light, no pre-mixing, and they are also good on gas.

On they way back from Fishtails at this years Vintage Challange, my 84 Liquifire had only used about 2 gallons of fuel. Stan could have made it back to the Whitetail with a half a tank to spare. Being able to use modern clutching should also help out the efficency too.

These are just my thoughts...

-Rainville

I have a OEM track made by yamaha, with a yamaha number on it 8J7-47110-00 that I'm not sure what it fits,nor does yamaha motor.. someone told me John deere, it has 35 windows, 15 wide.pitch is maybe 3 1/2 or 3 5/16..center to center of hole are 8 3/4,the holes (windows) are big, about 1 1/2 X 2 1/4...can anyone tell me what this fits...?kia392000@yahoo.com Don

Hello Don,

Deere never used a Yamaha branded track on their sleds, but both Deere and Yamaha did use Yokahma brand tracks. Deere used on 121x15"X3.29" on the 78 Cross Country Liquifire, and a 116"x15"x3.29" on the 80-84 Liquifire and 82-84 Sportfire. The Deere application used a unique drive sprocket pitch from Yamaha, (3.29" for Deere, 2.52" for Yami) and the Yamaha was driven off the center belt by two sprockets while Deere used three sprockets, one on each belt. The track clips to interchange however.

Also more thought on removing oil injection on the 80's Liquifires:

Most every Kawi motor I've ever had apart, including several Kawi Intuders, Drifters and Invaders, along with Deere Trail, Sport and Liquifires both with and without oil injection, all showed scoring on the inlet side of the piston. I am quite sure removing the injection will not fit that problem, but nicasil and chrome rings should.

-Rainville

I have a couple of the BM21187 56hp cc race kits for the 80 LF's and was wondering what the difference in the cylinders was. Was the porting different to work with the restrictor plates? I assume the clutch arms,primary and secondary springs were to compensate for the lost HP but what was the difference in the secondary buttons?

Sorry guy’s I don’t mean to hijack this post but the piston scuffing discussion interests me. I’ve been wondering about the typical failure mode and if there are symptoms that indicate this.

The two Liquifire engines that I’ve had apart have what I would call scuffed piston skirts but there was no damage to the cylinder bore. I’m assuming that when the scuffing is bad enough the piston starts transferring aluminum to the chrome lining causing reduced clearance and things just get worse form there.

If a piston is scuffed and has not started to damage the chrome lining of the cylinder does this cause any performance issues?

Nick

iajdsledhead wrote:I have a couple of the BM21187 56hp cc race kits for the 80 LF's and was wondering what the difference in the cylinders was. Was the porting different to work with the restrictor plates? I assume the clutch arms,primary and secondary springs were to compensate for the lost HP but what was the difference in the secondary buttons?

I also have a 56 HP kit for the 82+ Liquifires, as it has TR-800 calibration parts in it. From what I can tell, the jugs are ported for lower RPM torque, gives the sled better mid-range power. The restricter plates would limit the top RPM of the motor, so the clutching had to be recalibrated to compensate for the loss of RPM and HP. The secondary buttons were made from a smoother sliding nylon for less friction and better back shifting.

I hope this helps,
-Rainville

USCC VINTAGE CROSS-COUNTRY SLED RULES

In stock classes, no change or modification can be done to the snowmobile unless specifically allowed by these rules. If these rules do not specifically allow a change or modification, then it must be assumed that the change or modification is not allowed

STOCK CLASSES
1) VINTAGE
Maximum displacement is 440cc liquid cooled and 500cc air-cooled, 1981 or older leaf spring
models only.

2) VINTAGE LEGENDS
Same machine rules as VINTAGE, but riders must be age 50 or older at time of event.


GENERAL
1)The snowmobile must have the original OEM engine, hood, exhaust, frame, suspension and cowl. Replacement parts must be of same model and year.

ENGINE
1) Engine must remain in original mounting location
2) No component of the engine may be altered, changed or enlarged from the engine manufacturer’s original stock specifications. No removal of material whatsoever will be allowed.
3) Maximum cylinder overbore for wear or repair cannot exceed .020 inch.
4) There will be no more than one cylinder base gasket to a cylinder.
5) No modification to the carburetor body allowed. Jets and slides may be changed.
6) An adequate return spring on the throttle is required.
7) Choke mounting location may be moved for driver comfort. Choke system can’t be disconnected.
The exhaust system is to include any, header flange or pipe, Y pipe, expansion chamber, pulse charger, muffler and tail pipe that are original OEM equipment for that make and model. NO changes or modifications will be allowed to any part of the exhaust system or mounting locations.

DRIVE
1) Any OEM or aftermarket variable speed converters are allowed.
2) Any springs, weights or ramps may be used.
3) No machining on clutches to accommodate springs and weights.
4) In the primary clutch, metal may be removed but not added to ramps or flyweights.
5) Secondary clutch cams may be cut to any angle. Billet helixes allowed.
6) No overdrive machining.
7) Drive belts do not have to be OEM.
Chain case, drive shaft and drive sprockets may be changed to any OEM to accommodate track/brake changes. Shaft material may not be changed from OEM material for model year.
9) Any drive chain and sprockets may be used.
10) Chain tensioner may be changed to any OEM equipment.
11) Brakes may be changed or altered, but must be operational at all times. Brake components must be commercially available. Brake disk may not be modified in the pad contact area. Brake disk hub may be modified for mounting. OEM diameter and thickness must be maintained. The brake disk material may not be substituted with any other material.
12) Existing vents may be used to direct cooling air to the brake components. However ducting must remain under hood, and additional vents or scoops may not be added.

SKIS, SKI SUSPENSION, SKI RUNNERS AND STEERING
1) Front suspension must remain in original mounting location, in both bulkhead and spindle housing. No substitution of material allowed.
2) Reinforcement of components will be allowed by welding or bracing. Structural integrity must be maintained.
3) Spindles may not be shortened.
4) Ski stance must remain OEM center to center. No ski spreaders allowed.
5) Any ski shock allowed.
6) Any ski allowed. Skis may be reinforced on top-side only.
7) Ski skins allowed.
Ski loops leading edges on steel skis must be padded.
9) Any commercially available handlebar allowed. May be altered to fit driver. Open ends must be capped. Handlebars must be padded. Column or post must remain in its OEM position. Grips and controls may be modified. Throttle will be opened with a thumb mechanism (no twist grips).

TRACK SUSPENSION
1) Suspension must be OEM for the make and model. No material substitution allowed.
2) Rails may not be bent or shortened.
3) Wheels may be added or removed along with mounting brackets from an OEM wheel kit.
4) Any hyfax allowed.
5) Any spring may be used in the rear suspension. Springs may be shortened or heated.
6) Any commercially available shocks allowed.

TRACK AND TRACTION
1) Any commercially available, one piece track allowed.
2) Studs cannot be more than 3/8 inches above the highest point of the track.

FRAME & BODY
1) Snowmobile overall width is as produced.
2) Removal of any material from total machine by any means will not be allowed.
3) Skid plates may be added. Skid plates must be securely fastened
4) Additional plate material may be added to the tunnel at the suspension mounting holes.
5) Fuel lines must be free of obstructions by other machine components.
6) Additional OEM or aftermarket fuel tank may be added for additional fuel range. Additional tank must be securely fastened.
7) Seat padding may be added for additional driver comfort.

IGNITION & ELECTRICAL
1) Ignition must be OEM for the year and model.
2) Fixed ignitions may be moved (+ or -) four (4) degrees.
3) Wiring may be removed.
4) Head and tail lights must be original OEM equipment for the model and must remain in original mounting locations.
5) Headlight, taillight and brake light must be operational at all times.
6) Glass lenses must be taped with transparent tape. No colored tape allowed.
7) All snowmobiles must have a minimum of two (2) forms of ignition “kill” switch that must be operable at all times. One (1) form of “kill” switch must be a tether switch.
Maximum tether cord length will be 5 feet. The tether switch will be mounted in a location on the snowmobile other than on the handlebars or steering column.
9) The tether cord will be securely fastened to the driver. No alligator clips allowed.

Just wondering if this rule will be "equally" applied or only enforced on John Deere's? Sorry just dredging up old memories.

5) Headlight, taillight and brake light must be operational at all times.

DA

I also was wondering about the "At All Times" part of the lights ruling, Joe this probably needs to be addressed? it might have slipped by Jon??

Kenny

The USCC rep over on vintagesleds.com is already addressing that. They will change it to say the lights will only be required at the start of the race.

Here it Pat Mach's reply copied from VS:

Hey Guys,

A clarification is needed about the lights. The wording is not correct and I will get the change into ISR before the rulebooks go to print. The rule should read: "Headlight, tail light and brake light must be operational at the start of each race". So, if you finish the race without a hood or if you crash and the light breaks, you are ok and will not be DQ'd. With the modern sleds, the guys have to fix their broken lights in the one-hour repair session or else they are not allowed to start the next day. However, since the vintage race is only going to run one day, the only requirement will be that the lights work at the start of the race.

The race is tentatively scheduled for January 21-23, 2011. The plan is for the Vintage class to run on Saturday, the 22nd. It should be about a 170 mile day, with only 2 fuel stops so sleds will need to have a fuel range of at least 60 miles to make each stop.

Sorry for the mixup.

Pat Mach
USCC Racing

What about real early vintage racers that never had brake lights???

BU1 wrote:What about real early vintage racers that never had brake lights???

According to the rules, you would have to add one.

-Rainville

Joe, do you know how old a person has to be to race in the vintage class? 16?

Kenny