Guest Posted November 24, 2009 Share Posted November 24, 2009 HiBought this off ebay in a bit of a rush and bought a bit of a lemon ( broke my own golden rule and didnt inspect beforehand ). The previous owners have never owned a spanner me thinks!Now had terrible tickover probs, high idling, idle dying. Have sorted most off it out. replaced throttle cable/greased. replaced inlet manifold ( was full of holes ) serviced carb, everything blown through with carb cleaner etc. long winded story etc....Now thing thing thats puzzling me is, when I took it into the garage several weeks ago the guy said I had a weak spark. He replaced the cap/plug however they fowled VERY quickley ( hence I took it all apart to check properly afterwards ).Now would these symptoms be an iffy coil and lead. I beleive the fuel side is all ok tbh. I can see a spark when its grounded to the enigine but Im not really visually sure whats classed as a good spark and a weak one?Bike will tickover in the confinds of a garage for 10 mins ok but dies when idling outside within seconds. Will accelerate in 1,2,3 fine but in 4,5 really need to go gently up the throttle to coax a non hesitant speed out of it. Feels alot more hesistant whilst the weathers wet then gets alot better when its dry. I'm assuming that the wet weather affects the moisture quality in the air and if the lead/coil is iffy its having a harder job igniting it. Same goes for the fact it will idle in the garage as air quality good but doesnt idle outside? Given it a good rocking/shaking whilst ticking over fine in there and it continues to idle so dont think its a loose wire or anything.Any thoughts please?Many thanks for your time.SC Quote Link to comment Share on other sites More sharing options...
Guest Posted November 24, 2009 Share Posted November 24, 2009 air filter?? if its old and full of particles you will be pulling a high petrol, low air mix, damp air is heavier (particles/cm3) than warm air.. so harder to pass through a clogged filter.. good place to start anyway, and cheap enough. had one of these as a lad, nice bikes.. Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted November 25, 2009 Share Posted November 25, 2009 Fuel tank breather? Wet air apparently makes the engine run better. The moisture acts as a catalyst for the burn. What's the plug like? Quote Link to comment Share on other sites More sharing options...
Guest Posted November 25, 2009 Share Posted November 25, 2009 thanks for replies.no breather on the tank as far as I can see.plugs a little black at the ends quite new and can be attributed to ealier air leak/choke probs I think doesnt look enough to be renewable at presentoriginally had no air filter but now has a temporary one on, might look at changing that.all comments welcome. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 25, 2009 Share Posted November 25, 2009 thanks for replies.no breather on the tank as far as I can see.plugs a little black at the ends quite new and can be attributed to ealier air leak/choke probs I think doesnt look enough to be renewable at presentoriginally had no air filter but now has a temporary one on, might look at changing that.all comments welcome.ummmmmm, get a new one.... then see how things are, lets fix the obvious before we look for a problem that might not be there... Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted November 25, 2009 Share Posted November 25, 2009 The tank may vent through the filler. However..........The condition of the plug tells you what's happening in the combustion chamber. A little black means you're running rich. However without a standard air filter adjusting anything is pointless. Fit an air filter and clean the plug. You can't dig a hole in a different place by digging the same hole deeper. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 26, 2009 Share Posted November 26, 2009 correct air filter is on its way now however I asked them and they said it comes dry.having had a look in the old haynes manual it says that to oil it I should soak it in engine oil ( I use 10W/40SE in the engine, is this the correct stuff? ) and gently squeeze the surplus out?does this sound right to you? Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted November 26, 2009 Share Posted November 26, 2009 It looks like it's a foam air filter element. So soak in clean , new engine oil , squeeze out xs and fit. A more economic sysyem than a paper diposable element. Don't be too rough with it or it may tear and be useless. At service time wash and re oil. Simples. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 26, 2009 Share Posted November 26, 2009 and the above grade is ok, yeah?out of interest why do you soak it in engine oil or any oil, doesnt that just block the pores?sorry if thats such a lame question. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 26, 2009 Share Posted November 26, 2009 and the above grade is ok, yeah?out of interest why do you soak it in engine oil or any oil, doesnt that just block the pores?sorry if thats such a lame question. the oil sticks to the foam, but leaves airways, and dust will stick to oil, and yes, as long as the engine oil is clean (unused) you will be fine, some filters (K&N) have there own oil, but engine oil is just as good.. Quote Link to comment Share on other sites More sharing options...
Guest Posted November 30, 2009 Share Posted November 30, 2009 Have now fitted correct air filter and had it oiled.Also found the previous doughnut owner ( and then the motorcycle shop ) had fitted intake upside down eg facing oncoming air when it should be facing away ) guess the big 'TOP' sign was beyond their reading!New plug gapped and fitted too.Runs alot smoother and starts on the button, zero choke, and will happily idle in my garage for ages at 1300 revs, and returns fine. However took it out for 2 mins, pulled to side of road, idles about 1000 revs, so ok. Now back to whenever you pull the clutch in sits at about 3000-3500 revs for 3-5 secs then slowly drops. Out in this cold, doesnt tick over for more than a couple of secs once hitting the 1300 mark.Any thoughts please? Quote Link to comment Share on other sites More sharing options...
Guest Posted November 30, 2009 Share Posted November 30, 2009 Runs alot smoother and starts on the button, zero choke, and will happily idle in my garage for ages at 1300 revs, and returns fine. However took it out for 2 mins, pulled to side of road, idles about 1000 revs, so ok. Now back to whenever you pull the clutch in sits at about 3000-3500 revs for 3-5 secs then slowly drops. Out in this cold, doesnt tick over for more than a couple of secs once hitting the 1300 mark.Any thoughts please? hows the choke cable, is it sticking on, take it off and lube the cable.. you need to leave the choke on for a short while to let the engine warm up, before heading out... Quote Link to comment Share on other sites More sharing options...
Guest Posted December 1, 2009 Share Posted December 1, 2009 no choke cable just a pull switch, that seems fine as the engine picks up when its on from cold then drops back when bikes been warmed.my problem with the revving at idle seems to be after its done a couple of miles and warmed up if anything.cheers Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted December 1, 2009 Share Posted December 1, 2009 The first part of the choke opens the throttle to increase revs. After that it chokes off the air. If your choke is a lever on the carb there will be no cable. A pull on the bars will be connected by cable to the carb. Check the throttle is returning and the choke isn't sticking. If that checks out, warm the bike up and adjust the revs with the throttle stop screw. Quote Link to comment Share on other sites More sharing options...
cooper99 Posted December 2, 2009 Share Posted December 2, 2009 check your pilot jet in your carb... its the little one, and your pilot mix screw, i think it should be 1 1/2 turns out, but double check that, i had one of these bikes as a kid, Quote Link to comment Share on other sites More sharing options...
Guest Posted December 4, 2009 Share Posted December 4, 2009 realised now that the tickover is fine both indoors and outdoors but the 'raised revs' issue starts as it warms up, going to and staying about 3-4k revs when fully warmed. May occasionally die back to 1300 normal.its a new intake manifols and everythings screwed as tight as poss.the bike runs fine apart from this Quote Link to comment Share on other sites More sharing options...
Guest Posted December 4, 2009 Share Posted December 4, 2009 realised now that the tickover is fine both indoors and outdoors but the 'raised revs' issue starts as it warms up, going to and staying about 3-4k revs when fully warmed. May occasionally die back to 1300 normal.its a new intake manifols and everythings screwed as tight as poss.the bike runs fine apart from this probably needs a good run, to clear itself... Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted December 4, 2009 Share Posted December 4, 2009 Make sure the throttle is returning. Something may be snagging. Try pushing it back by hand at the carb end. Cable or twist grip may need lubrication or cable internal may be damaged.Nearly there Quote Link to comment Share on other sites More sharing options...
Guest Posted December 10, 2009 Share Posted December 10, 2009 Back again guys...continued thoughts please if poss?Found original carb had a busted mixture screw, just spun and spun, so that looks like the 3k rev on idle prob.Have changed and fitted with aftermarket replacement carb. Everything blown out with carb cleaner. All air filter, manifolds back on rock tight. Now starts very easily and will tickover arount 1500 revs on idle. Little slow returning to idle when revved up but for now easily liveable. Whilst idling adjusted screw by ear until highest revs then lowered with idling stop screw. Best when turned out quite a bit more until it started slowing down again. This is all whilst warmed up. Havent been back out on it yet.Now only slight issue is that when its at 1300 revs in idle will drop down to around 900 revs then slowly surge back up to about 15-1600 then drop down ( and repeat ) will die off every so often.Now when riding it just before this change I thought my weak spark was a problem but after fitting the correct air filter is ran though all revs pretty much fine. So my though is whether the weak spark is causing the surging or the die off eg not strong enough to keep it ticking over?Cheers Quote Link to comment Share on other sites More sharing options...
Chrissb6 Posted December 10, 2009 Share Posted December 10, 2009 You might want to check the fuel flow line. It might be the case of fuel starvation as if the engine is hunting for fuel, ie the revs are going up and down, as the fuel flow slows down the mixture will run week making the motor run fast and then die. This could be due part due to a block fuel line. Check the fuel tap and strainer and make sure you have a good flow. As Colin and others have mentioned also check the tank breather this might be a pipe or a pin hole in or around the filler cap this sometimes get choked in polish and crud.Sounds so much to me like a fueling problem.Best of luck as it sounds like you covered all the corners Quote Link to comment Share on other sites More sharing options...
Guest Posted December 10, 2009 Share Posted December 10, 2009 i still think it needs a good run out to clear any carbon from running like it was... take it for a good run down a dual carriageway and see if that sorts the matter out..a weak spark would cause cold starting issues.. Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted December 11, 2009 Share Posted December 11, 2009 Could be a faulty battery or loose terminals or a bad earth somewhere, but it does sound like a fuel problem. Red X it and give it a good run. Quote Link to comment Share on other sites More sharing options...
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