750 Zane starter ratios and stuff

Even though I have a good PC 680 the engine can be sluggish at one point but my engine starts within 2 seconds
Terry Sage has recently had his Formula starter overhauled for £40 plus his new cables and his starts incredibly smoothly - it was serviced by a Denso dealer - I have witnessed this starting
Clearly the ease of starting is also a function of clean injectors , good plugs and good fuel
 
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I always started the bike, but it would stall trying to get over TDC at times, excessively stressing the starter and sprag, the injectors, plugs and fuel were all working as per spec. The starter just couldn’t get the engine spinning easily enough. Although I’ve had the starter cleaned and replaced the brushes with an extra two brushes added by myself, it’s always an option to get it serviced, the new battery is supposed to arrive tomorrow, so we shall see what the weekend brings!
 
yep, thats right Adam the starter does benefit from the 4 brush conversion as well. It is a lot easier to live with now, just hope i am finally there as far as running and starting issues are concerned
 
Quick update! I have all back together, starter gear, and pc680 battery etc as per previous!
First impressions are positive, the motor turns the engine easier and as a result faster, although it can still stall on TDC, but nothing like it was doing!… that’s the good news.
It now has a fuelling issue, it just starts and no more, either stalls itself, or, if you even touch the throttle it dies immediately.
Since this bike has sat for a good few years, I suspect the fuel supply system, rather than faff about, I’m on the verge of removing the tank and replacing the pump, filters and relays. I have stuck a gauge on the supply line and when the pump does the initial prime it’s making 2.5 bar, not sure that’s enough.
Does anyone have any experience on pump replacement, do I really have to remove the tank altogether to do this?
What is controlling the initial prime, I have run the fuel pipe from the pump to an open container so it would not cause a back pressure, but it only runs for a few seconds, I thought there would be a pressure switch detecting the pressure and switch it off?
Any easy way of checking the injectors and or cleaning them?
I am determined to have this on the road again!!!!
 
The fuel pressure regulator is set at 43.5psi as on the markings on the throttle body pressure valve of 300KPa which is 3Bar. 2.5 Bar should be enough to start it then the pump will need to be running else lack of pressure will stall it - does the pump run when it has started? By design when first turned on the control computer runs it for just a few seconds to build that starting pressure. That 43.5 psi is necessary to get enough fuel sprayed in when the injectors are opened for the time set in the fuel mapping else not enough fuel will be delivered.

I expect you'll need to get the injectors cleaned as well as the pump and filter attention - I have tried to do pump etc. replacement with tank in place but my fat hands don't allow that and the tank has come out for that job or at a minimum the subframe loosened and injectors lifted away so that you can get to that front plate where the fuel pipes connect to the injectors and return line. That takes some hours. If the throttle body is off then it's easy enough to take it to an EFI specialist and have them hooked up to a cleaner and calibration check machine - they are standard injector connection plugs.
 
It might not be that easy as for sure you have replaced the complete fuel, but it sounds so similar to how my Forumula behaved that I wanted to check: When I started my Formula first time after 5 years of standing in the rear of my garage, it had very similar issues. touching the throttle made it cut out instantly.

I removed the fuel completely (put a loooong fuel-line into the tank through the filler, sucked the petrol until it started running and filled everything into another tank. Made sure really almost every drop of fuel got out...). Then I re-filled with fresh top quality fuel. took still several attempts (fuel in the hoses between tank and injectors), but when the old, bad fuel was burned, it reved as it should and started really instantly! Next time, the cold start was a push on the button...
 
My Kawasaki (which is like a bronco in that it wants to spit me off, as soon as I ride it) While not fuel injected, has a fuel pump. It sat idol for some time and the fuel was bad/off. I drained the tank and hot wired the pump, collected all the foul smelling shit and disposed of it thoughtfully.
I ‘thought’ about it ‘fully’ and poured it onto some weeds down the back yard.

It stank for weeks and even the neighbors asked if we could smell it.

Every brass part in the carbs had a green growth on them. Yamaha has a carb cleaner/soaking fluid that worked a treat.

Back together and away it went.

But, thinking about the gunk inside makes me think the injectors contraptions you are talking about would probably have the same green shit through them too. It may take a lot of fuel flow to clear it.
 
I would go with Lothars suggestion - use some injector cleaner in the first tank - if you have to go the pump route - walbro do a version , exact replacement specs could be found on Zanelist groups .io with a search. Make sense to do the pipes as well as these are teh ones the ethanol attacks
 
I’m in agreement with everybody here, I’ve started the tank removal, got sidetracked by a bottle of beer or two, now will replace everything, from pump to injectors, and that means clean the injectors, I’ll let you all know how I get on!
 
Kennyrnut said:
I’m in agreement with everybody here, I’ve started the tank removal, got sidetracked by a bottle of beer or two, now will replace everything, from pump to injectors, and that means clean the injectors, I’ll let you all know how I get on!
Click to expand...
Ok all, I’ve eventually got the work done.
New fuel pump, new fuel filter, new hoses, new pc 680 battery, check throttles, new upgraded battery to starter cables, converted starter to a four brush, fluid service, and fitted the modified ratio starter gears from 3cmoto as per previous post.
The difference is tremendous starts on the button no problems.
I have attached a short video, excuse the filthy state of the bike, first time it’s been out in daylight in 11 years!
View attachment IMG_0958.MOV
 
That’s an excellent result ! Mine has the hesitancy that you said you had but starts within a second so I am
Living with it - Check the connection to the regulator behind the seat pad - this can be a source of a screwed battery - the generator is running continuously and in pretty well every Zane that connection is fried !
 
Sir Sidney Ruffdiamond said:
That’s an excellent result ! Mine has the hesitancy that you said you had but starts within a second so I am
Living with it - Check the connection to the regulator behind the seat pad - this can be a source of a screwed battery - the generator is running continuously and in pretty well every Zane that connection is fried !
Click to expand...
Oh yes, that regulator connector has been seen to already. Hopefully that should be the last of the big ticket items to get it back on the road.
So shiny bits to fit and a good wash and polish next.
 
Update,
After all the works done,…. starter gears, battery cables, new pc680 battery, 4 brush conversion to starter motor, new fuel pump, hoses, filter and injector clean,…. The bike started very well, as per the video, however possibly due to the starter gear improvements the, sprag free wheel clutch has now given up.
So I can confirm that the KTM part number 58440026000 fits perfectly, and has actually improved the starting further, it’s instantaneous now.
Now we need to see if I rides as well as I rennet it!!
 
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