Leaky Exhaust

"Dear Ralph" October 28, 1997 0
Dear Ralph: My ’94 Vmax 500 has a continual leak at the Y-pipe area. Oil is dripping down into the belly pan and sure makes a mess. I’ve already installed new gaskets, but still have the problem. Any suggestions ? Even though new gaskets are used, you will sometimes... Read more
Dear Ralph: Are there advantages of the rotary intake that Rotax uses on many of their twin cylinder engines ? Are rotary equipped engines more powerful than piston ported or reed intake designs ? First let’s compare the rotary intake to a piston ported engine. The advantages of the... Read more
Dear Ralph: I have a 1995 Indy XLT and the head gasket keeps blowing out. What is the solution to this problem? You’ve got one of two problems. Most likely is that the water (coolant) filter is partially blocked (plugged) and the coolant flow is reduced. This reduction in... Read more

Flooded Engine

"Dear Ralph" October 28, 1997 0
Dear Ralph: I have a flooding problem with my engine. If the sled sits for a while without turning off the gas, the crankcase gets quite a bit of gas in it. J. Barsness One of two things is happening. We had a similar problem on one of our... Read more
Dear Ralph: What is “tunnel porting” ? Is this only a Ski-Doo thing ? Lee Kempffer To be accurate, tunnel porting is performed on rotary valve intake engines, and since Ski-Doo is the only sled maker using this type of intake, it is a “Ski-Doo thing” . This procedure... Read more
Dear Ralph: What is the difference between Mikuni VM38SS and VM38AL carbs ? I thought that the XLT Special and XC 600 were using the same engine, but the SP specs say it has SS carbs, and the XC says AL – what gives ? Nothing more than an... Read more

Single Pipe Doubts

"Dear Ralph" October 28, 1997 0
Dear Ralph: I’ve heard somebody say that it is nearly impossible to get over 110 horsepower out of an engine with a single pipe. If this is the case, then how are we to believe that the MX Z 670 and SX 700 produce around 115 hp ? It’s... Read more


"Dear Ralph" October 28, 1997 0
Dear Ralph: My Indy Classic seems to have a problem with the throttle override kicking in at low rpms which causes the engine to backfire. Is there any way to unhook or disconnect this system ? Under no circumstances (other than in an emergency to make it home) should... Read more

Longer Break In ?

"Dear Ralph" October 28, 1997 0
Dear Ralph: I’ve heard that these new “Nicasil” cylinder liners have a longer break-in period than do the cast liners. How many miles should I wait before I change jets and expect full power from the engine? It isn’t so much breaking in the cylinders as it is to... Read more

Idle Too High

"Dear Ralph" October 28, 1997 0
Dear Ralph: Why would my ’96 XLT have an unusually high idle speed? A high idle is usually caused by a lean condition. Most people remedy this by turning in the air screws a bit (1/4 turn more) which enriches the idle mixture, but this varies from machine to... Read more