Novice question: How to seal up flex pipe, exhaust spitting

[Jeff Spencer]

New to the sport, I appreciate your patience, experience and advice.
I think I need to refresh the "wrap" around the flex pipe. Can I get what I need at a hardware store? Is that just fiberglass, & ?, are there good DIY alternatives.

Second question, how much is too much "exhaust spit"? It seems to me that we are getting a lot of blow by. For practice, I am running pump premium and 8oz per gallon of good 2 cycle racing oil, I think it is a Motul product. I guess I am asking if I went with 7oz/gallon, would that reduce the spit? Or if I use a higher octane racing spec fuel, will that make a difference? Also, would there be a noticeable improvement in performance and fussiness of the Gazelle?
jws

[Steve O'Hara]

The type of gas and the amount of oil in your fuel mix is not the cause of the leakage at the flex. You are running the engine too rich on the carb settings or maybe just driving too passively. Avoid letting the engine idle or using part throttle as much as possible. Unless you are running in very cold weather you can just start the motor and GO.... no warmup needed. When driving the kart use full throttle or no throttle/brake to control the speed.... avoid part throttle even when driving in the pits.

Properly tuned and driven you won't need any cover at the flex as the exhaust will be dry.

Warning!! When you have a lot of residual fuel coming out the exhaust flex there is a high probability that you also have a buildup of residual fuel laying in the bottom of the crankcase and that can create some tuning challenges. It is pretty common for new karters to get their motor loaded up with residual fuel which makes the engine four cycle (blubber) and smoke a lot so they lean the jets beyond the correct setting and the engine will run fine for a while but eventually it will clean out the excess fuel and the mixture will be too lean and you'll need to re-adjust the carb or you'll damage the engine.
I would recommend you make sure the engine does not have a bunch of residual fuel by draining it. Just remove the spark plug and wrap the plug wire in a rag so it can't spark to any nearby metal, remove the fuel line and then flip the kart over so the spark plug hole is pointing to the ground and crank the starter for 10 seconds with the throttle wide open. The proceedure will blow any residual fuel out and you'll be able to start fresh knowing you don't have a small lake of fuel in the bottom of the motor.
I would also remove the pipe and dry out the header and the flex before running.
Good luck.
Steve O'Hara

[Jeff Spencer]

Thank you, much appreciated. It sounds like you have some experience, I appreciate your willingness to help out.

I have a few follow up questions:
1. I have heard of folks running fuel mixtures of 6oz/gal -- 8oz/gal. What is a good mix?

2. I have researched and found that initial ballpark settings of the H L needles of 1 1/2 L, and 5/8 -- 3/4 H. From these initial settings, what would be a maximum amount of adjustment turning of each needle. What increments should the adjustments be made in. How does weather impact the adjustment of the settings?

3. How does pop off play into all of this? I have a gauge to measure this, but I have absolutely no clue.
jws

[Paul Makarucha]

I use a PBR can myself.


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Do you have any special rituals when the helmet is concerned like many have? - "I wipe it so that I can see better." - Kimi

[Jeff Spencer]

Hmmm, PBR might be a little upscale for my for the way we roll.
jws

[Jim White]

[John Mulvihill]

Hi Jeff,

Which motor?

John
_________________
I bowl overhand..........

[Jeff Spencer]

IAME Gazelle