Low end bog

[titanic]

Not sure of the difference but the 640 uses BR9ES

[CShark44]

I recently installed a SBT 650 cc in my 94 Tigershark Barracuda. It runs great once you get on plane, but won't jump out of the hole. Factory setting for high and low needle are only 1 turn, and I am now all the way to 1/2 turn on my needles, and plugs are still fowling. {black and wet} Any ideas would be appreciated. [img]redface.gif[/img]

[Bryan Glynn]

What plugs and gap are you running, how long did it sit between engines, and how did the original fail?

[CShark44]

The local Tigershark dealer keeps giving me NGK--#BR9EYA, not sure on gap, I have them check them when I buy them. The original motor went because the previous owner didn't winterize 1 winter, and the crank brgs. rusted, then eventually let go. It only sat over the winter. Thanx for quick reply!!

[CShark44]

Guess I'll rebuild the carb and see what it does. Any suggestions where to get a kit?
I know the stock plugs are BR9ES, these are suppose to "BURN CLEANER" according to dealer. Thanx for replies ! [img]tongue.gif[/img]

[Bryan Glynn]

Well, if it's sat all winter, and obviously now all spring and into summer (and I suspect it was actually from last fall, not winter) then you are due for a carb rebuild - since it was not winterized.

[Bryan Glynn]

You need a Mikuni SBN rebuild kit - we have them for $30.

[titanic]

IMO you should use factory (Suzuki) recommended plugs to increase accuracy of pinpointing problem.

[SteveStL]

I have a 97 shark with a 640 motor. The NGK--#BR9EYA is the correct plug, though they tend to get a little oily I wipe them off before each ride. The 640, though spirited, doesn't have the a 'killer' hole shot. I believe they sacrificed hole shot for better speed in the case of 640's. The 97 pump may differ from your ski but I am assuming that they aren't that much different. If the engine is running well you may want to consider a Solas prop to see if you can get a better take off. See what their web site recommends. On my 640 I'd say I'd hit 0-30 mph around 3 seconds, something like that - maybe less I'm guessing. I have a top speed of 45-47 mph.

Good Luck
Steve