polecat Posted July 13, 2011 Share Posted July 13, 2011 (edited) So you open the throttle and it feels like it wants to let go but is being held back Can Bad plugs make this much diference to performance or is it going to be something else more hard ? Edited July 23, 2011 by polecat Quote Link to comment Share on other sites More sharing options...
Guest Hodgy Posted July 13, 2011 Share Posted July 13, 2011 I doubt its plugs else it would be missfiring, have you kinked a fuel hose restricting the petrol flow to the carb(s) perhaps, or maybe they need balancing if you have 2, or just need adjusting? Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted July 13, 2011 Share Posted July 13, 2011 the tappets could make it run like that as the vlaves will not be opening fully if they are loose(out of adjustment) Quote Link to comment Share on other sites More sharing options...
Tango Posted July 13, 2011 Share Posted July 13, 2011 Could be plug or HT Lead or coil. If the plug is fouled or just old it can cause it to hold back a bit when you put the engine under load.I always work on the principle of doing the easy stuff first before looking for a more complex problem. New plug = 5 mins work....fixed? Yes - Happy days..No - Check next thing (Clogged air filter, clogged fuel tank breather, clogged fuel filter..etc)Use the KISS principle.. Bob Quote Link to comment Share on other sites More sharing options...
polecat Posted July 13, 2011 Author Share Posted July 13, 2011 Could be plug or HT Lead or coil. If the plug is fouled or just old it can cause it to hold back a bit when you put the engine under load.I always work on the principle of doing the easy stuff first before looking for a more complex problem. New plug = 5 mins work....fixed? Yes - Happy days..No - Check next thing (Clogged air filter, clogged fuel tank breather, clogged fuel filter..etc)Use the KISS principle.. BobGood thinking batmanIll change the plugs and work from there but Maby the tappets causing it or carb sync,thanks Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted July 13, 2011 Share Posted July 13, 2011 Service it. Give it a full service Quote Link to comment Share on other sites More sharing options...
Fozzie Posted July 14, 2011 Share Posted July 14, 2011 All she needs now to be spot on is clean balanced carbs, a healthy valve clearance and some fresh iridium plugs (Greatly help carbed bikes especially with cold starts)Its almost there for being a showroom condition bike! Quote Link to comment Share on other sites More sharing options...
Tango Posted July 14, 2011 Share Posted July 14, 2011 I guess the other thing about the valve clearances are if they are negative (valves not closing fully).....can lead to burnt valves.I think CtB is right....a good ol' service will do it a power of good!Bob Quote Link to comment Share on other sites More sharing options...
polecat Posted July 15, 2011 Author Share Posted July 15, 2011 I think to save my sanity I will book it in for valves adjustment and carb sync then do the rest my self It will be interesting to see what diference the plugs make but I only got the standard ones to start with cos I'm tight Quote Link to comment Share on other sites More sharing options...
Roadtorque Posted July 15, 2011 Share Posted July 15, 2011 best place to start, change the plugs, if ones not firing properly the the mixture is not burning correct & the engine feels sluggish with no power,,,I had a new Breva only did 500 miles & a plug went, it was like an old pig & every thing they said about Guzi went through my mind,,, New plug = New bike was right as rain after that Quote Link to comment Share on other sites More sharing options...
Carlos Von Brum Posted July 15, 2011 Share Posted July 15, 2011 Stoopid question...Checked your air filter / choke? Just suggesting to check the air, as will as the spark. You've not got a pigeon in your airbox have you? My FZ gets a bit like that if I forget to take the chocke of, sometimes. CvB Quote Link to comment Share on other sites More sharing options...
Colin the Bear Posted July 15, 2011 Share Posted July 15, 2011 Don't give in now. The stuff you've already done is way more complicated than adjusting valve clearances. Balancing a twin is only one adjustment. Have a go. Follow haynes, easy peasy Quote Link to comment Share on other sites More sharing options...
polecat Posted July 15, 2011 Author Share Posted July 15, 2011 Stoopid question...Checked your air filter / choke? Just suggesting to check the air, as will as the spark. You've not got a pigeon in your airbox have you? My FZ gets a bit like that if I forget to take the chocke of, sometimes. CvBYou could eat your dinner from the inside of my Airbox New filter in there and oiled up as the one in there when I got it was full of holes and about 50 beech leaves Don't give in now. The stuff you've already done is way more complicated than adjusting valve clearances. Balancing a twin is only one adjustment. Have a go. Follow haynes, easy peasyYour right Colin the plugs came today and they look hansome compared to the ones in the bike so Ill change them then look at the tappets this weekend Quote Link to comment Share on other sites More sharing options...
Roadtorque Posted July 16, 2011 Share Posted July 16, 2011 Stoopid question...Checked your air filter / choke? Just suggesting to check the air, as will as the spark. You've not got a pigeon in your airbox have you? My FZ gets a bit like that if I forget to take the chocke of, sometimes. CvBYou could eat your dinner from the inside of my Airbox New filter in there and oiled up as the one in there when I got it was full of holes and about 50 beech leaves Don't give in now. The stuff you've already done is way more complicated than adjusting valve clearances. Balancing a twin is only one adjustment. Have a go. Follow haynes, easy peasyYour right Colin the plugs came today and they look hansome compared to the ones in the bike so Ill change them then look at the tappets this weekend Bet you it's the plugs Quote Link to comment Share on other sites More sharing options...
polecat Posted July 18, 2011 Author Share Posted July 18, 2011 I am going to put them in today So Fingers crossed !bloomin Rained since they arrived so not had a chance yet Quote Link to comment Share on other sites More sharing options...
polecat Posted July 23, 2011 Author Share Posted July 23, 2011 So I changed the plugs for New ones and it has made no difference ....SO for all you mechanics out there I am now looking for the next solution I emptied the float chambers and there was no dirtI took out the new plugs and the ends are white coloured but not fouledI did notice the gasket on the bottom of the float chamber is leaking (could it be drawing air in and making it run restricted)I am getting a friend to help me adjust the tappets (incase thats the problem)When looking down the left plug port I did notice what looks like an offset washer inside (which was not on the right side) and wondered if that is actually a part of the engine in the wrong place or os that normal Any other Ideas what it could be if none of the above ? I have the day off today and will try and sort it out if I know what I am looking for. Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted July 23, 2011 Share Posted July 23, 2011 what you could see might of been one of the valves open turn the engine over slowly with ign off and bike on centre stand put it in 4th or 5th gear will turn easier then see if the 'washer' moves up and down otherwise if it is sat on the top of the piston itself then no its not meant to be there and will mean cylinder head off as it could have a broken valve in the head Quote Link to comment Share on other sites More sharing options...
polecat Posted July 23, 2011 Author Share Posted July 23, 2011 what you could see might of been one of the valves open turn the engine over slowly with ign off and bike on centre stand put it in 4th or 5th gear will turn easier then see if the 'washer' moves up and down otherwise if it is sat on the top of the piston itself then no its not meant to be there and will mean cylinder head off as it could have a broken valve in the headYikes Ill go and do that ........Edit : yes I did turn it and the washery thing vanished ...phew (never seen one of them in there so it worried me ) Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted July 23, 2011 Share Posted July 23, 2011 then take bike for a run and once you have done a few miles take the plugs out and see what colour they are at the tip that will help find out if mixture is out at all Quote Link to comment Share on other sites More sharing options...
polecat Posted July 23, 2011 Author Share Posted July 23, 2011 then take bike for a run and once you have done a few miles take the plugs out and see what colour they are at the tip that will help find out if mixture is out at allyeah I did 28 miles yesterday and the plugs are quiet clean still but a whitish colour on the metal bit over the electrode and that is not listed in the haynes manual at all ....its all grey or sooty or oily in the manual and mine as I said is clean but whiteish,the electrodes look like when I put them in Quote Link to comment Share on other sites More sharing options...
eastanglianbiker Posted July 23, 2011 Share Posted July 23, 2011 whitish normally meansbike is running weak on the mixture and if very sooty then its to rich normall meant to be a lightish brown colour check mixture settings on carbs.if the haynes manual shows you which screw on side of carb is the mixture then screw that right in and then back out 1 1/2 turns on each carb and see if it runs any better.also is it points ign system or electronic if its points they could be pitted and worn out Quote Link to comment Share on other sites More sharing options...
polecat Posted July 23, 2011 Author Share Posted July 23, 2011 Tappets are now done ! YAY another DIY job learned(They were too tight)I think I know which is the mixture screws and might play about with them tomorrow If not then I reckon it must be ignition timimng or blocked Jets Quote Link to comment Share on other sites More sharing options...
Tango Posted July 23, 2011 Share Posted July 23, 2011 Yeah...if the plugs are whiteish when you take them out it points to running too lean. Are you running standard exhaust? Quote Link to comment Share on other sites More sharing options...
polecat Posted July 23, 2011 Author Share Posted July 23, 2011 Yeah...if the plugs are whiteish when you take them out it points to running too lean. Are you running standard exhaust?Its a standardish MOTAD 2 into 1 instead of the original 2 into 2It does not have any points I belive...think it is the CDI box thing ? Quote Link to comment Share on other sites More sharing options...
Guest Hodgy Posted July 24, 2011 Share Posted July 24, 2011 Before adjusting the mixture, try running it again now you have adjusted the valves, it may have just been that Quote Link to comment Share on other sites More sharing options...
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