mad mart
Guest
hi all, can anyone enlighten me as to why i have black sooty secondary sparkplugs,bike seems to run fine. also,do valve clearances get larger or smaller with miles done? might be daft question! cheers martin. 
RickG
Registered user
No idea why you have sooty plugs unless you looked at them after letting the bike tick over and not after a good blast. Plug-chops to determine mixture strength from colour are normally done when the engine is hot and without letting it idle. Most new engines run lean and the plugs will have few deposits and appear a light grey
Traditional wisdom suggests that valve clearances reduce early-on as the seats bed in and thereafter increase as all the bits slowly wear. In practice on modern engines this can't be relied on to be what you'll actually experience. I find, over 6000 mile checks, the exhaust clearances usually get bigger and inlets do whatever they feel like.
Traditional wisdom suggests that valve clearances reduce early-on as the seats bed in and thereafter increase as all the bits slowly wear. In practice on modern engines this can't be relied on to be what you'll actually experience. I find, over 6000 mile checks, the exhaust clearances usually get bigger and inlets do whatever they feel like.
mad mart
Guest
sparkers
thanx rick, i did find the inlet valve clearances smaller and exhaust were ok.,bike done 12k. primary sparkplugs were a lovely tan colour as you suggest but secondary plugs were both sooty black,the bike had just come back from spirited ride and wasnt left to idle. have new airfilter installed and have replaced all s/plugs so will have to see what happens. bike been running fine even with sooty secondary plugs,MYSTERIOUSLY.
thanx rick, i did find the inlet valve clearances smaller and exhaust were ok.,bike done 12k. primary sparkplugs were a lovely tan colour as you suggest but secondary plugs were both sooty black,the bike had just come back from spirited ride and wasnt left to idle. have new airfilter installed and have replaced all s/plugs so will have to see what happens. bike been running fine even with sooty secondary plugs,MYSTERIOUSLY.
thanx rick, i did find the inlet valve clearances smaller and exhaust were ok.,bike done 12k. primary sparkplugs were a lovely tan colour as you suggest but secondary plugs were both sooty black,the bike had just come back from spirited ride and wasnt left to idle. have new airfilter installed and have replaced all s/plugs so will have to see what happens. bike been running fine even with sooty secondary plugs,MYSTERIOUSLY.
Something to think about are the coils to the secondaries. I am not sure what they are on the 1200 but I had a primary coil go on my 1150 and the bike still ran fairly well. I felt that it was an issue with the TBs. Dealer couldn't find any fault on diagnostics but I eventually found the coil had gone by using a spark tester between the coil and plug. Just my 2p worth!
Let us know how you get on.
OldCroc
mad mart
Guest
thanx oldcroc, could be coils will investigate,let you know. cheers martin.
The secondaries to be sooty is normal ,its because they don,t fire at all rev ranges.
It's worth taking a close look for corrosion of the secondary coils, the steel sleeve on both my lower coils was badly corroded and the left hand coil plastic casing had split wide open where the coil laminations had rusted internally and expanded. A new lower coil is £69 inc vat. The left and right lower coils are different part numbers as they point in differing directions unlike the primary coils which are straight.
The secondaries to be sooty is normal ,its because they don,t fire at all rev ranges.
Parkys that's quite interesting - do you have any more info on that - eg which rev ranges etc?
OldCroc
mad mart
Guest
The secondaries to be sooty is normal ,its because they don,t fire at all rev ranges.
thanks parky for your input. sooty plugs are definately not normal. I know that for sure after changing my mates plugs on his gs12,the x2 secondaries were a nice tan colour albeit a very slight shade darker. valve clearances are fine,airfilter new,bike uses no oil. will have to drop the new offending plugs and see what state they are. coils seem suspect,will test for spark also. cheers martin.
WorkyTicket
Registered user
Is there a special tool for putting in and taking out the plugs?
I'm using a long reach 10mm plug spanner from Halfords but having a nightmare trying to get the right hand primary back in.
I'm using a long reach 10mm plug spanner from Halfords but having a nightmare trying to get the right hand primary back in.
RickG
Registered user
A 3/8" socket set with the correct spark plug socket works well for me, though it does have to have narrow enough walls to keep the diameter down otherwise it'll get caught up on the inside of the head as the plug screws in.
The BM one from your local dealer is around £10 IIRC. Fits, does the job, not too expensive either
by chance i have put a new set of plugs in my 1200 today. these are what i took out after 17500 miles:
Primary
Secondary
as you can see, the bodies of the secondary plugs are darker than the primaries. the important indicator, the insulator nose is roughly comparable.
ps. in theory, valve clearances should close over time. valve springs stretch the valve stem and hammer the valves into the heads. for them to get bigger, you need cam and valve train wear.
in theory
pps. i used a snap~on 3/8 spark plug socket. Fits, does the job, <s>not</s> too expensive
Primary
Secondary
as you can see, the bodies of the secondary plugs are darker than the primaries. the important indicator, the insulator nose is roughly comparable.
ps. in theory, valve clearances should close over time. valve springs stretch the valve stem and hammer the valves into the heads. for them to get bigger, you need cam and valve train wear.
in theory
pps. i used a snap~on 3/8 spark plug socket. Fits, does the job, <s>not</s> too expensive
mad mart
Guest
thanxs cookie,those plugs of yours look the same as the ones pulled from my mates gs,secondary plugs a shade darker. my secondary plugs are both real black n sooty but bike runs real fine actually feels stonger slightly than my pals. got feeling there be no sparking going on so possible coils fault, still open to any good ideas tho. cheers martin.
D6
Registered user
The secondaries to be sooty is normal ,its because they don,t fire at all rev ranges.
. got feeling there be no sparking going on so possible coils fault, still open to any good ideas tho. cheers martin.
Simple check - pull the two main caps off and see if it fires and runs with just the secondary plugs in.
mad mart
Guest
what a brill idea steptoe,sometimes its the simplest way of doing things that can be so easily overlooked....too obvious. will try,and let you know when ive finished the washin up,ooverin,feedin the dog.walkin the dog,de-fleein the cat,puttin kids too bed,readin stories,waterin the plants.puttin the cat out and if any energy,seein to the wife. 6x pints of lucozade barman,for the energy....
I've seen it written that this can damage the disconnected coils 'cos the spark has nowhere to go
Was on an american forum - I will try and find the link and post it.
OldCroc
I've seen it written that this can damage the disconnected coils 'cos the spark has nowhere to go
Was on an american forum - I will try and find the link and post it.
OldCroc
certainly the advice given for for some ignition systems, applies to R100, not sure about the 4v models. to be sure to avoid damage, just stick a plug in the cap and ground the body.
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