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Fuel or ignition


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I am trying to get the ESD on the road. Engine rebuilt, everything adjusted as per manual. Carbs spotless, factory airbox installed with filter.

This am I finally got to take it for a spin, but she is gutless! Fires up at the flick of the button, idles nicely at 1100rpm.but as soon as you hit about 4-5000 she stutters and feels/sounds like a twin! So I went back home effortlessly, got out infrared temp gun and sure enough #4 was not as hot as the others. I could sizzle spit on all except #4. Ok I said, maybe I forgot a vacuum port, nope. Hmm, maybe a piece of shit got in the pilot jet, nope, even swapped it with #1, no joy. Ok, let's pull the carbs and try a set off a gsxr1100. Well she barks with those! So I take #4 off the rack, break it down and blow the shit out of every passage, but it all flows well. Passage from neddle jet to pilot circuit is clear, air jet for pilot circuit is clear as are all passages. So I adjust float heights to 20mm, reassemble, install and run. NFG, FFS!

ok, relax, change the coil, no better FFS!

I yank all 4 plugs, 1 and 4 are black while 2 and 3 are light grey. Something is fucking with my little brain and I am getting pissed!

so, can it be the Ignitor? But why did it run sooo good with the other carbs, maybe because there was no filters? I just slid them in the carb boots and fired her up.

Right now I am thinking ignitor, all the same I am going to grab 4 new plugs tomorrow. Right now I just have the plugs that came in the bike, and from my research they are incorrect, they are dpr9es, supposed to be d8es?

thanks for any help!

 

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Blackened 1 & 4 does sort of point to plugs / leads / coil. The plugs may be salvageable but cleaning blackened or fuelled up plugs never seems to work - new plugs different story! If there are ANY electronics on the bike don't use D8ES plugs - you need DR8ES's ie. resistor plugs else the RF interference from the D8ES's will mess with everything.

Of course swapping the carbs in the garage and having them rev clean ain't the same as out on the street and under load so it still could be a duff carb - but do the simple stuff first!

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Tried new plugs, no change, FFS! So as far as I am concerned I have done the simple stuff first.

so I just tore down a spare set of bs34ss carbs, I will put through the sonic cleaner on Monday and see what that does.

I put one of those jumpers that goes from the lead to the plug and spark was jumping a .040 gap, so I am thinking the ignition is good, at idle anyways?

Can anybody think of anything other than the carbs?

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Changing the plugs is one out of three - Leads rarely fail partially but not impossible. What about the coil - have you tried another? As they are supposed to fire two plugs, your's could be breaking down just enough to randomly fire either 1 or 4. All carbs should be set the same - only rarely do you up the mains in the centre pots due to heat build up

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I pulled the carbs, again! Getting good at it now tongue.png.

I now have my ignition problem sorted, bad ignition leads, or maybe just loose. I fooled around with it and it is running same temp on headers at idle.

However, at around 5000 she stutters, I am now thinking it is too rich on the MJ?

So, according to the FSM, I should have 112.5 main jet, it has a 122.5. Pilot jet should be a 45, I have a 47.5. Main air jet should be 1.2, I have a 1.6. The markings on the jets are CIB? Anybody ever heard of these? 

When end I got the bike it had crap pods on it, I have since installed the factory airbox setup. I also have a set of 1150 cams installed, set to 105-107' IIRC, it's recorded somewhere.

So, I have done some research and from my readings it seems it is a good idea to go up a bit on the main and pilot jets to make the engine run better, in stock configuration, meaning stock airbox and maybe headers, which I have. But the readings say to go to a 115-120 MJ. 

I have adjusted floats to 22mm, as per manual

I have a set set of Mikuni 115 MJ I am thinking of giving a go.

Advise pleaseredface.png

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IMHO with an essentially stock engine, it should only need stock jets. An end can change shouldn't need much of a jetting change - even cams with stock inlet / exhaust won't change much as the breathing isn't much improved outside of the cylinders. But a K&N (say) in the airbox and a full exhaust in association with the cams will deffo benefit in good dyno set up.

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Well, those 115 jets got her up and charging! :banana:

After I installed them I re-sync'd the carbs, set idle. Then had to run to my daughters grad dinner. Got her out for a short blast and she works great. But I noticed the idle increases when warmed up so I need to richen the pilot screws a tweak, tomorrow's job.

The bike handles and feels absolutely fantastic, pics to follow.

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So, I am out 3.5 turns on the pilot screws, starts no problem, as she pretty much always did. However, she still rises to approx 1500 once hot, after 20 minutes of hard driving. 

They are the stock pilot jets, all new OEM carb boots, factory air box. She also has an off idle hesitation when hot, but pulls hard once 3-3500 rpm has been reached. A feathering of throttle at hot idle is required to get off the line smoothly.

The hesitation is not there when the bike is cold.

Bike has 4:1 Wolf exhaust with a very quiet pipe for a 4:1!

47.5 is the pilot jet, maybe move up to a 50? I do not want to come out more than 3.5 turns on the screws as they seem loose right now.

What I found odd was very little change at hot idle from 2.5 to 3.5 turns.

 

 

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On 6/23/2018 at 7:40 PM, Fjbj40 said:

Tried new plugs, no change, FFS! So as far as I am concerned I have done the simple stuff first.

so I just tore down a spare set of bs34ss carbs, I will put through the sonic cleaner on Monday and see what that does.

I put one of those jumpers that goes from the lead to the plug and spark was jumping a .040 gap, so I am thinking the ignition is good, at idle anyways?

Can anybody think of anything other than the carbs?

Manifold O rings ? Fucked me around on my GS1000E  revs like a fart out of a bath tub but soon as there is load its dead as a door knob till i changed the o rings between head and manifolds . 

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No o-rings on the 16 valve 1100.

So I found an article that said to rich on the pilot circuit with these particular carbs can also cause the problems I am having.

So for shits and giggles I set the pilot screws at 1 turn out, gonna take it for a run a little latter tonight to see the results?

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I never tried as just warming it up in the shop yielded no change >:(   So, I decided to make tooling to check fuel level in the bowls. Glad I did because even though floats were set the level was below limits! Fixed that and she was working very well.

Took her for a good heat up and all seem to be working just fine after resetting the pilot screws. Was on one last hard pull to check main jet and needle height. As I pulled out and cracked her she was pulling beautifully and I was thinking to myself ahhhh got it! Then all of a sudden baaaaaaa, no more ignition, she just quit. 

So, checked fuse for ignition, that's good, checked my Newell installed ignition relay, yup that's good. And that's as far as I got. Going to check the Ignitor and pickups later today.

FFS!

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Short found! The screw holding the coil power tang backed out and shorted against the mounting stud. Fixed with lock washers and added best shrink to stud to prevent a possible repeat.

I am getting tired of working on this one so I took the hooligan 1000 out for a blast today, picture added to the cool air-cooled bikes post :tu

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