Surging H2

[Baz]

OK not a big thing but it can catch you out, my H2 has a sharp surge at low speeds, it will tick along quite nicely then will give a sharp burst and then go back to normal, my thoughts were along the lines of;

an air leak or a dodgey lead from the coil to the spark plug?

Any help would be great, nearly went arse over tit the other day

[autofobe]

Welcome to the life of the H2 Driver. a little better tuning can get rid of most of it but at slow speeds
You will have to live with it.

Brad

[Baz]

Thanks, It's a bit different to the normal missing and farting it normally does while you're trying to cruise at 50 or 60KPH, this is at walking pace putting it in the garage or idling up the driveway and my driveway is dirt and the burst will spin the wheel

I might sinc the carbs again to see if it makes it a bit better and also change the intake rubbers, I got some new repo ones from cruzinimage a while ago.

Thanks.

[mraxl]

kawatriple.com/faq.htm#surging

A carb kit from Ivans Performance will also cure surging.

[kawonda750]

Aug 25, 2021 5:42:51 GMT -5 mraxl said:

kawatriple.com/faq.htm#surging

A carb kit from Ivans Performance will also cure surging.

Baz, these carb kits work wonders. A little expensive but they are worth every penny. He gives you jets and needles for every exhaust/ intake combination.

[autofobe]

Sometimes going up a fraction on the pilot jet helps.

Brad

[norm]

Aug 24, 2021 21:26:14 GMT -5 Baz said:

Thanks, It's a bit different to the normal missing and farting it normally does while you're trying to cruise at 50 or 60KPH, this is at walking pace putting it in the garage or idling up the driveway and my driveway is dirt and the burst will spin the wheel

I have Ivan's kit on my 73 H2A and find it really helps eliminate the lean surge in the mid range and cruising situations. I have a stock exhaust and air box and I also continue to use the stock 35 pilot jet  ... given what you have written above, I am wondering if you have a throttle slide prone to sticking .. I would check to ensure all the slides move freely all the way up and down.  

[horster]

I can attest to the improvement in performance using Ivans jet kit. My H2B surged violently at low to medium speeds where the engine is lightly loaded. Ivan's kit did not fully eliminate the surging, but did reduce it considerably. The magnitude of the surging dropped significantly and the frequency of surging went up. Keep with his recommendations for which jets you need to install based on what other changes you made to the bike. I found that closing the idle mixture screw to less than Ivans recommendations only caused the engine to "stumble" on acceleration from a stop. 

[kawonda750]

I was wondering if you have the little wire clips in your throttle cable at the adjuster on the carb. Maybe your throttle cable is not returning all the way down.