richyrich

So what was my total pain in the ass nonstarter has now done a few hundred cold miles, making a lot of noise ! that acrapovich can on the gsf600 was loudish, on the 750L it is brutal. I am growing to love this thing again. ive had to learn how to ride again after being very upright on the dr350 and using a h**** duuurvelle for work in town, it feels lithe and crisp and sexy in comparison. Now the tarmacs been a bit warmer ive been trying to loose the chicken strips. Anyway now it wont go into gear without stallng out so looks like she's eaten her clutch. Obviously i only found this out on the road and not first thing before leaviing the house. Fortunately this happened right outside hart council offices and copshop, so i felt very safe test riding it, as it got worse and worse going round the carpark trying to figure it out. It was like a fuelling problem, i thought, popping and banging and surging, with all the schoolkids running about, before finally i realised i couldnt get it in gear any more. The coming pain is totaly worth it for the last few weeks of blissful speed, power and tinitus. Just hope its not been nicked overnight when i come back for it tommorow.

The conclusion to that chapter was actually a little more nuanced than just the plugs. Id noticed it was constantly overfueling, which i puzzled over alot, Turns out the float valves werent sealing, the needles were not long enough to sit in the valve seats. i dont want to mention how i managed to mix up two different old and new sets of float valve parts to achieve this mismatch

well Toni that was my initial thinking so thanks for the input and your totally right FBOBandit but ive given the sodding thing to a bikeshop now. In fact the dude from the new bikeshop just called and he was like "started right up wassa problm" !!!! So credit were credit is due; CAPNCHAOS said " just put new plugs in" and sure enough all new bike shop said it'd done is put in new plugs. G*d*m M8th(u*RS eretceterea and so on and so forth... i am hanging head in shame ein the moments betwen dancing manically and necking stellas. So sorry for getting everyone excited i have been banging head ont wall over this for tiiiiime, i appreciate the ideas guys people who've looked at it before have said get new plugs but ive got 8 friggin plugs with zero miles on em and i just cant believe it wouldnt even pop and bag and try to fire, i cant find a good explanation of why zero miles plugs can be fecked by cranking ot over ???? still here we are the man said it runs. i might even relax and start to believe... mot next week, gs back on the road woohoo

good one solcambs that is a mindfeckin inspiration. Im just gonna ditch the goddam key now. Hell im gonna start work on a wireless loom. Bloody resistors. thief proof chldproof bkes goddam owner proof grumbl grumble

thanks for the replies guys. I really appreciate the offer fatblokeinbandit, its been a bit low round here with this mystery going on. You and capnchaos both agree that 750L ignition key unit pluged into b12 loom wont work, i wil look into this and try to figure out how that is. Meantime ive found a workshop that seems keen and has pic of a gsx1100 streetfighter on the webpage cover, they do mots and welding etc. Ive got faith they know these bikes and won try and sell me a new one. So with any luck it'll puzzle them and then i can step in to solve the problem hehe

I double check that every time i look at the damned thing. I remembered its not the original loom, i think its an american b12 one cos it has a pink wire which i saw somewhere is for a fuel gauge. If it is that one and ive plugged the 750l ignition into it, is there the hotwire resistor thingy fucking it up? Maybe i should just change out the loom, wtf. Its also got a koso speedo-tacho wired up to the remains of the old instrument loom. Not using the supplied scotxhlocks. Its all gotta come out again, thinking out loud

Im having a nightmare trying to get my bike started, ive written a few things in diff posts and had some helpful feedback. Today ive run out of ideas so im starting this thread and putting all the details together in the hope you guys can help. back in 2004 i had trouble starting a 750L so i put in new piston rings, that raised compression from 100 odd to 120 plus, but it still wouldnt start, i tried new plugs wih it then moved on and put it away. Later on i got a gs550 with a b6 enigne andn running gear, worked lovely for years. Last year i put the 750 in, it worked once, i cant remember what if aythign was different that time. Ive just come back to it. im using a 100 amp hour car battery to spin it over. Starting with compression of 120, 100, 50, 120. i got nothing turning it over, so i swapped the old green dyna coils for the bandit ones. It coughed and spluttered trying to fire. so i took out the motor, removed the head and lapped in the exhaust valves. Put it all back together and it doesnt even try and fire. I had both cams 1 tooth out with the arrows pointing horizontal and not at the gasket , so sorted that out and moved a couple shims. COMPRESSION: now it turns over and compression of 135, 140, 150, 135. valve clearances in spec. If the valve timing was wrong it would not have these numbers, the valves are opening and closing fully in the right order. With the way these engines work that has to be right ? I got it wrong once now its right. If id eg mixed up the cams or was tripping looking at the arrow marks or whatever, it wouldnt turn over or have compression im pretty sure SPark: Ive tried two pairs of coils, both have reistsance within spec as far as i can tell. Ive put new 5kohm plug caps on the bandit leads to replace the original 11kohm ones thinking it might give a better spark. Bar the old, but barely used plugs ( ive got eight cr9 eks so far) , what can be wrong with the HT system ? It sparks away happily, something should go bang, it should at least try and fire surely... FUEL: The bst 38 has a bad reputation in my research for running wthout its airbox, some people get them working. Today i put on the b6 keihin 32mm carbs that used to run quite happily with pod filters. The tank petcock is flowing well also. Still no attempt to fire its not fucking magic, its an engine, its science, its got good fuel, good compression, its got a spark, hard to say if its a good one its not orange its bright bluey white. Perhaps its not happening at the right time ? so what controls that ? i thought with this engine theres no control over the ignition timing with stock parts. So to my tiny mind, theres three things. 1 the intake valves somehow. 2, the loom ive puled about to fit it in, but it wouldnt even spark or turn over or have lights if id shorted and fucked it somehow. 3. the spark is at the wrong time! Thats the spinny thing on the right, how can that be wrong, its the original 750 one, with the original 750 Loom, and a replacement 750 cdi. theres no witness mark of it being filed down i can see. Maybe its mounted wrong, i havent checked, is that possible ? what the effing hell is going on

haha doesnt very good does it "cleaning plugs with nail file.." So Yes Capn a fine idea, but ive already got 8 cr9 plugs. They're 15 quid a pop. the second set of four have about 2 miles on them, the first set zero miles but some minutes of stationary running. I would happily shell out for plugs if there was any sign of the thing trying to start. Id be overjoyed if it fired at any time ! its a real problem, several people have said to me; get new plugs. As i understand it theres stuf, maybe seleniumin and other shit, in fuel that coats the electrodes if it is not burnt off when the motor gets up to operating temperature. But if it never runs thats not going to happen so what to do. I cant spend fifty quid on plugs every time i want to turn it over. How can i clean the plugs ! I use a small bronze brush, contact cleaner and a little kiss with a very thin (nail) file to try and clear this coat of fuel shit. if it was regulalrly coughing and spluttering trying to fire id get new plugs but its not, theres something else.

yeah thanks Crass, i thought i mightve had a good idea, one of those things thats wrong and you walk past everyday without noticing. I went out and "earthed" coils with some jump leads and it didnt fire but i thought the spark looked slightly bluer, the power of the mind go figure. its true that it did try and fire immediately after swapping the coils three days ago. which it hasnt done at an other time. i feel like this is a clue. other variables associated with that are the Lt connections and that id just cleand the plugs with a nail file. FML

uhuh, thats how they do possibly not for much longer in this one after i torch it and chuck it off a cliff

what a nightmare, stuck on the roadside, how do cdis fry up. im no expert. thats gotta be too much amps or volts or something.. isnt the reguator in the alternator assembly in these engines, is it letting too much "electric" out ? or can coils try to "pull" too much curent through. Still your 750L starts up, i cant get mine out the garage haha

do i need to earth coils through the mounts or do i need to insulate them cos they earth through the ht lead. im having a nightmare starting this 750L engine. im worried about the spark now... i had old green dynas on it, got this thing out for first time in months and swapped them for bandit coils, just connected the low tension and layed them on the frame. I thought it had a much bluer spark, put the plugs in and the thing tried to fire, popping and banging. Great i thought, thats new. mounted them with a long bolt and piece of rubber tube as a spacer to lift them over frame and insulate from vibration as much as volts. spark back to white again. Im really clutching at straws here. timing good ie cams and crank synched right with timing marks and chain links. compression cold is 140 in all four cylinders. bit subjective what is a white or blue spark, its flipping sparking goddamit. is making an earth through the coils what im doing wrong ? something is wrong and i cant see it

could the ht lead be shorting accross a wet cam cover surface ? a film of condensation over the metal and the lead be sat in a drip of water, a nice hydrocarbon vapour mix built trapped in the breather filter ? the bike will be fast, its eager !

i think i had keihins on y b6 runing ok with pods. i'll check tommorrow

Thankyou jameskat, colinworth and captn chaos. The litany of confusion goes like this: The Timing was in fact one tooth out ! fixed that, got some compresion back. Then the valve clearances did look different to before the valve lapping, so swapped some shims about keeping notes, veery interesting. torqued the cam caps and great; closed a loose one and opened a tight one; but hang on, valves ive not touched have tightened up s what the hell is going on. Id let the cam chain tensioner extend then screwed it in, this tightens clearances in the middle. Probly shouldnt admit to that but dammit that was a long hour. Reset the tensioner and presto all valves in spec and compresion of 135, 150, 140, 135. I think thats healthy enough for a cold test. Tommorrow it might even start...

yeh exactly, do the valves start hitting the pistons if its 180 out tho, i think they do, mus be right

thanks, yeah the clearances havent changed at all, which im a bit miffed about, i figured number three exhaust valves would tighten up with amount of flippin twig rubbing lapping i did on them to make a nice seat. The timing marks and number of chainlinks are all good im pretty sure, obv willl double check again tommorrow. Can they be 180 out ?

thanks, yeh i wondered about the compression gauge before on something else, it is a screw in one and the carbs are off. The readings are pretty consistent accross all four tho so i dont see the gauge not working. interesting about brocken rings, but that would be apparant straight away wouldnt it ? in a single cylinder. ive gota measured thirty psi missing on all four. that had been there on diff tests months apart. and yeh bad form on the head gasket but the engines not under any load cranking over on the starter with the plugs out, i dont wanna believe its blowing. But hey the pressure gotta be going somewhere. Tommorro im gonna retorque it. Ive got faith in the valves and the piston rings, the cylinders had a bore when they went in. The head gasket is the prime suspect. Its the inner two that lost compression, one each before and after the head came off. Maybe that is the pair and theyre blowing into the cam chain tunnel. fuckety fuck fuck. as the sod isnt actually running would i see evidence of this blow by on the gasket i wonder. I really dont want to take the fucker out again.

compression numbers measured cold with opem throttle,1-4 l=r after new piston rings, fitted a year ago 120, 130, 135, 120, with oil in bore 160,150,155, 160 trouble starting all year after instalation, zero mies covered recently 130, 125, 50, 130 and valve clearances: exhaust 25/25 25/25 30/30 25/25 intake 15/30 15/20 20/20 20/20 lapped in exxhaust valves, couldnt shift intake valves with my old tool, now 100, 50, 70, 100 with oil in bore 100, 90, 100, 100, valve clerances have not changed can anybody suggest why ive lost compression ? i got number three back presumably cos the exhaust valve seats better, but ive lost number two. i dont understand why all four are down,. I wonder if the head gasket and head have seated properly. ive reused the head gasket and this is the second time its been off. it is torqued down correctly. it shouldnt be blowing by with no plugs in and just the compression tester. i am stuck. id really apreciate any ideas

for my 750L Im working on the assumption that an oiled kandn type filter would give more reistance to air flow than a foamy ramair, and therefor have characteristics marginall more favourable to an engine designed with an airbox. Im trying this wih bst38s that it has started and run with ramairs, on a 4-2-2 exhaust, standard pilots and 135 mains. It was a bitch tho. Im trying at the moment with a 4-1, kandn dual pods and some other stuff for better compression and spark. i had bst34s on a b6 running on the same 4-1 exhaust with 4 pods reliably. Its interesting what you say about the slides lifting too early and people taping filters. How is it goin wiv the starting and running ?

ive got a troublesome 750L to. I found that replacing the old green dyna coils with the ones from a b6 gave a much bluer, better spark. The dynas gave a 2ohm primary resistance vs the 3 their website ses they should have and a 12 ooo ohm secondary resistance, which is in spec. The suzuki coils also gave a 2ohm primary resistance but 40,ooo ohm secondary, both are in spec. I dont really know what all that means. i like fat blue spark, still wont start it tho the f***** i think b6 coils are the same as b12 coils, i read that somewhere but havent checked part numbers. maybe theyre cheaper. stick coils twenty quid a pop when i looked at them

hi i had a dream my newly fitted 750L engine and its mikuni bst38 carbs worked ok with its ramair filters, in the gs550. It wasnt a dream it ran from cold and i even rode it once. Now it wont start.... Nikos1400 started a good thread in November about this and the conclusion was, the 38s' are a nightmare and new plugs and battery sorted him out. I cant be throwing new plugs in to watch them get fouled in short order. My HT is good and the battery should be good enough as it turns it over hard. Its interesting that the one time ive ridden it, i started it plugged into the shops bigass charger, so new battery is probly good advice but not the whole answer. which has got me thinking. So back to carburation. Its got 155 main jets in it, which should match the ramair socks as a starting point. It drives me crazy cos for a while it started and idled, quite high idle and its like the throttle cable was sticking, but it proved it worked and i got on with putting the rest of it together. The only thing ive changed since those long gone easy start days is stupid shit like wiring in tail lights and my deluxe wooden tank mount. So what gives... Its the fouled plugs from starting it and not riding, getting it up to temp to burn off the foul deposits, the shit. So its constantly flooding and the spark is not strong enough to ignite it. This is an interesting article......http://tonysleep.co.uk/info/great-gsxr400-carburettor-saga Hes basically saying the o rings keeping the fuel in the float bowl from the charge get imperceptably knackered and let loads of fuel through. Thus making the metering of the starting and main circuits kinda pointless, as it will be way too rich anyway whatever tune you do. So my plan is to pay a well known manchester carb o ring supplier, as recomended by robinsons foundry, a lot of money for a small amount of well formed, petrol resistant, rubber. then see if my spark is good ebnough to start it. What does the oss hive mind think of this plan and about the above article. Good day chaps

can someone remind me what the pickups are please ? if i look under the ignition cover, where the spinny ignition advancer thing is and it all looks the same on both engines, its all good right ? cheers guys

do i need to swap ignition advancers or pickups or something to get this working ? I'll probly try both cdi's see if i can tell the difference someone here knows, thanks guys