anyoldiron Posted September 1, 2017 Share Posted September 1, 2017 I have a new to me 1984 Vf1000F with 48k kms that ive been resurrecting. It was all dirty forgotten about and needed rescuing. It was only running on a couple of cyls, given the smell of the gas and time standing its a miracle it ran at all. The carbs where a mess, they where stripped cleaned with lacquer thinners, and compressed air. New main, pilots jets (Honda) , throttle valves, bowl gaskets, pilot screw o rings (aftermarket) . Assembled correctly with the correct mains, springs and needle jets in correct places. New intake manifolds, clean air filter. Carbs synced with Manometer. The problem; The bike fires right up, and revs ok on the stand. When riding it will cruse along at highway speeds ok, but if you lean on the throttle it takes off in fits and starts. I have tried this in all low gears opening the throttle full, it will surge and falter at different points. Or if you will there is no constant point in the rpm range that this will happen...............the only time when it seems to pull almost right constantly is at hi rpms in 4th.......maybe 5th, but space is a issue to check 5th properly. If you roll on the throttle gently the same thing will happen...............it feels like its running on 3 and a bit most of the time, with it feeling like old school turbo kicking in when it runs correctly all plugs are equal and ok (a tad rich) accept for the rear left #1 cyl which is moist and sooty. All four cyls will steam a wet rag at the top of the exhaust. Valves done, clearances adjusted New plugs , swapped around Compression 150psi give or take 2psi on all 4 cyls Float height set 7.5mm New battery Clean tank, lines in tank blown through with air, new fuel lines, filter and CBR pump that works, module thingamagig bypassed. Tank breathing Ok. Coils swapped over, also wires swapped over Carbs cleaned again, checked setup again. Equal pulses from both exhausts Cleaned checked earths Please, before you say carbs, i have 27 bikes, including a CBX and KZ1300s, these carbs are a walk in the park compared to KZ1300 carbs, i know its not a ultimate qualification, but i spent the best part of a day cleaning them, so while its a possibility its carbs, im thinking its electrical, bad carbs have a more consistant problem areas in the rpm range , if you know what i mean. .......................and im at best a smart monkey when it comes to electictrickery. .......................what have i missed? Cheers AOI Link to comment Share on other sites More sharing options...
Member Contributer Captain 80s Posted September 1, 2017 Member Contributer Share Posted September 1, 2017 Pulsar coils under right crankcase. Bolted around starter clutch housing where they sense a couple triggers. This is where I would take another set to test, but not everybody has spares like this. There are resistance and continuity checks in the FSM, but they are not 100% conclusive. They can give symptoms you describe and can often be affected by heat when going bad. Link to comment Share on other sites More sharing options...
anyoldiron Posted September 2, 2017 Author Share Posted September 2, 2017 Thanks for your help Captain. l cannot give you any info as to whether it deteriorates when it gets hot as i live 2 miles down a gravel road, its warm by the time i get up to the highway. l will check the pulsar coils RR etc etc and report back. l understand what you mean with electrictrickery components on these sort of things, they can give different readings cold, hot under load l will go through the electrical connectors end to end just to be sure Link to comment Share on other sites More sharing options...
Member Contributer wpbarlow Posted October 1, 2017 Member Contributer Share Posted October 1, 2017 Anything to report back on this? Link to comment Share on other sites More sharing options...
VF1000Fe Posted October 1, 2017 Share Posted October 1, 2017 Since there are 2 pickup coils, you can Scope each, compare wave-forms. You can just ohm them out too, but those answers are usually not definitive. Since it works intermittently, I think the pickup coils are fine. The Spark Boxes provide the Power (and Advance). Ohm out and Scope at the coils. Since you're close, I have spares of Everything, if you want to borrow some Pickup Coils/Spark Boxes for diagnostics. Link to comment Share on other sites More sharing options...
anyoldiron Posted May 22, 2018 Author Share Posted May 22, 2018 Hello, So some follow up on the VF saga. We have seasonal riding here and i needed the arseometer for testing on this so ive only just got back to it. lts turned out to be poor/crapped out pulser coils ( ones on the right hand side). l swapped them out for a good pair. The carbs also got cleaned again just to be sure due to the purchase of a ultrasonic cleaner over the winter, as well as all electrical connections rechecked,cleaned by scraping and cleaner spray. There is now a massive improvement, rode it for 120kms today, it pulls cleanly through the gears to near the red line, well up until 3rd as i like my licence. lt does not pull away in top from say 80kmph in top as clean as i would like, but i have yet to sync the carbs properly properly with the manomter and solder the ign wires, but im being ultra picky, i think its in the tuning due to being able to 'ride round the issue' by slowly opening the throttle rather than cracking it wide open, Anyways. Thank you for all your help, and your kind offer vf1000fe job well done, well almost, its classic bike ownership, is it ever done Link to comment Share on other sites More sharing options...
Member Contributer Dutchy Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 16 minutes ago, anyoldiron said: job well done, well almost, its classic bike ownership, is it ever done short answer: no Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 19 minutes ago, anyoldiron said: Mean looking bike, great job. Is that an optical illusion or do you have some form of over-sized front tire? Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 16” front wheel mate. That and a wide lens makes it look bigger. Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 17 minutes ago, VFROZ said: 16” front wheel mate. That and a wide lens makes it look bigger. Thanks mate, now, I know you're a very clever fella, but how the hell ya know its a wide angle lens. Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 My other hobby is photography.😉 Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 And I had one Link to comment Share on other sites More sharing options...
Member Contributer Grum Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 51 minutes ago, VFROZ said: And I had one Mate that's a great lookin bike, even in wide angle. Is that an optical illusion or is that front tire sooooo much smaller that the rear, don't answer. I know I know it's the wide angle. LOL Bet ya wish ya still had her! Cheers. Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 Back in its day it was a real mile cruncher. A bit of a nervous front end, but a great sounding bike. I wish I had all the bikes I’ve owned. Specially my GPz900R, or my Laverda RGS1000. Sorry for the thread hijack. Link to comment Share on other sites More sharing options...
anyoldiron Posted May 22, 2018 Author Share Posted May 22, 2018 Nope, it’s pretty stock. Running better still, pretty much there now. Link to comment Share on other sites More sharing options...
Member Contributer Terry Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 I resurrected a 1990 ST1100 that had been parked up for 10 years and thought I had a dirty carb fault as it would cough and fart any time I tried to rev over 4000rpm. Pulled those darned carbs out/apart 6 times! Turned out to be as simple(?) as a dirty electrical connector that was preventing the full 12V reaching the ICU, giving poor sparks at higher revs. Like you, I pulled every connector apart and cleaned it plus dielectric grease, along with the chassis grounds, and the bike runs like a new one now. Link to comment Share on other sites More sharing options...
Member Contributer VFROZ Posted May 22, 2018 Member Contributer Share Posted May 22, 2018 Congratulations. Looking good. It is always a pleasure to clean an old girl up and get it running again. Grum might have been on to something, what size is that front tyre? it looks very tight on that guard. Have you opened up the valve covers to look at the cams? Link to comment Share on other sites More sharing options...
Member Contributer wpbarlow Posted June 2, 2018 Member Contributer Share Posted June 2, 2018 Good looking bike & congrats on the rescue! Walter Link to comment Share on other sites More sharing options...
Member Contributer VF1000RS Posted June 6, 2018 Member Contributer Share Posted June 6, 2018 Good Looking F. Link to comment Share on other sites More sharing options...
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