HELP??????????

[Nitro boater]

Wat is it that determian how fast or how qiuck your nitro motor get on to the pipe (outboard K&B 7.5cc)

 

[Geraghty]

Wat is it that determian how fast or how qiuck your nitro motor get on to the pipe (outboard K&B 7.5cc)

Design of the boat.....weight of the boat.......design of the pipe........length of the pipe.......

glo-plug range.........needle setting...........carb size.........timing numbers on the motor......

diameter and pitch of the prop and set-up of the boat,I.E. motor height and thrust angle.........

Probably the four biggest factors to consider are the carb size is to big,prop is to large,the pipe is to short and the needle is to lean.......

Violate any of the four and you will have a driveability problem on your hands.

I am sure I have missed something :wacko: .....Good luck.....

 

[Nitro boater]

Wat is it that determian how fast or how qiuck your nitro motor get on to the pipe (outboard K&B 7.5cc)

Design of the boat.....weight of the boat.......design of the pipe........length of the pipe.......

glo-plug range.........needle setting...........carb size.........timing numbers on the motor......

diameter and pitch of the prop and set-up of the boat,I.E. motor height and thrust angle.........

Probably the four biggest factors to consider are the carb size is to big,prop is to large,the pipe is to short and the needle is to lean.......

Violate any of the four and you will have a driveability problem on your hands.

I am sure I have missed something :wacko: .....Good luck.....

Im runnig the standerd carb,you arent the first guy that told me that my carb is to big,should i go for the 3.5cc carb?

 

[Geraghty]

Wat is it that determian how fast or how qiuck your nitro motor get on to the pipe (outboard K&B 7.5cc)

Design of the boat.....weight of the boat.......design of the pipe........length of the pipe.......

glo-plug range.........needle setting...........carb size.........timing numbers on the motor......

diameter and pitch of the prop and set-up of the boat,I.E. motor height and thrust angle.........

Probably the four biggest factors to consider are the carb size is to big,prop is to large,the pipe is to short and the needle is to lean.......

Violate any of the four and you will have a driveability problem on your hands.

I am sure I have missed something :wacko: .....Good luck.....

Im runnig the standerd carb,you arent the first guy that told me that my carb is to big,should i go for the 3.5cc carb?

I never told you that your carb is to big,just be aware of that it is one of the four major causes I was eluding to.

There are [2] different stock K&B 7.5 outboard carbs.The newer 7.5 billet 9400 series carb has a bore of .375" .The older cast body 7.5 outboard carbs have a stock bore of .312".There is no 3.5CC carb that will fit in your motor without a custom machined adapter.

What is your carb bore size???If your carb has not been modified in some way and it has the bore dimensions I have listed,it should be ok.

To start I would pull the pipe out a bunch [maybe a 1/2"] and put on a much smaller prop and see if that solves your"get on the pipe faster"problem.

If it does help the problem then I would start adding back pipe and prop slowly,"DOING ONE THING AT A TIME" until you reach your goals

Look,there is no magic bullet to this problem.....you are going to have to get on the water and test and get some experience changing your set-up paramaters to determine the best way to achieve your goals.

Send me a photo of your boat and motor and I will give you a good middle of the road starting point on your set-up.

[email protected]

 

[Nitro boater]

Click on my name and the pictures are there

 

[Geraghty]

Click on my name and the pictures are there

I sure can't find them.....send them to my e-mail address

 

[Nitro boater]

Click on my name and the pictures are there

I sure can't find them.....send them to my e-mail address

I HAVE UPLOADED IT YESTERDAY

 

[Jerry Wyss]

Click on my name and the pictures are there

I sure can't find them.....send them to my e-mail address

I HAVE UPLOADED IT YESTERDAY

I saw your pics of your 7.5.. The pipe length looks a little long to me but that wouldn't stop the engine from performing

fairly well. I will say that those engines have to be in near perfect running condition to get the most out of them.

There's alot of places on model boat engines that can make them run strange,, air leaks on that engine are usually the culprit,

and thats not the normal flow for a needle assembly. Also I run a small less pitchy prop on a mod motor, like an Octura 447.

Can't quite see what your prop is,, it looks almost too small in the pic.

 

[Nitro boater]

Click on my name and the pictures are there

I sure can't find them.....send them to my e-mail address

I have uploaded the new pics have a look