Bigwol Posted August 16, 2015 Share Posted August 16, 2015 I got into this Yamaha owners thing by accident last year. A friend of mine had bought a 1991 Yamaha XJ600 Pre Div in 2013, spent a year trying to get it to run, and partially succeeded - (It might deign to run when the weather was dry), but he got fed up with it refusing to run if there was even a smidgen of moisture in the air. The straw which broke the camel's back, was the day it was booked for an MOT and, (it being a rainy day) the thing wouldn't start. Various teddies were thrown out of prams, and my friend said, "if you want it, you can have it for what I paid for it, I've had enough!" Since said friend had just replaced the exhaust with a Motad 4-1 and replaced the front forks for an (allegedly) better pair. it seemed like a reasonable offer, so - never being one to refuse a challenge, I bought it, and christened it 'the two wheeled paperweight',The XJ600 wa un-MOT'd, so I SORN'ed it, and had it transported up the M5 by van, and dropped off for further investigation. True to it's reputation with my friend, the XJ600 flattened two batteries trying to coax it into life, and remained sullenly unstartable. Checking out the options, revealed that the fabled 'igniter' - or TCI box, was high on the list of suspect parts, - as my checks showed that the primary and secondary resistance of the coils seemed OK, the plugs were brand new and there seemed to be plenty of fuel sloshing around. So I bought an Ignitech TCI-P4 transistor ignition unit from Ignitech in Czechoslovakia, (nice guys!, recommended), and plugged it in, (having charged the battery in the meantime). This resulted in much more spluttering, and half hearted attempts to run, though still sounding very much like it was trying to run out of petrol. So the carbs came out, while I looked up 'how to service Mikuni BS32 carbs'. The wildlife I found in the carbs was unbelievable! Each float bowl was half full of a red jelly like goo, (ethanol problem?), and each jet and filter was clogged up with the same sort of crap. To be honest I couldn't see how the thing had fired up at all, with the crud in the carbs,right through from the float bowl, through main jet, pilot jet and enrichment assembly. Over the next couple of months I became rather more familiar with the internals of Mikuni BS32 carbs than I had intended, but eventually reached the stage where all the o-rings had been replaced and things looked pristine, and all the important little places had been blown through with carb cleaner, so, after linking the carbs back up into a bank of four, and solving the mystery of where the 3mm detent balls, springs and 'choke rod' assembly went, I had something which looked like it should work. It sort-of did, - by which I mean that it ran on three, with number 4 cylinder refusing to join in. Stripping the carbs again revealed nothing nasty, so I put them back in, fired it up and this time, number 3 cylinder was the one not playing. Since the coils were 1&4 and 2&3 I thought I would find out whether we had an ignition problem or a fuel problem, and switched the LT input to each coil, and also swapped the plug leads, effectively changing the coils over betweenom 1&4 and 2&3, The problem stayed with number 3 cylinder. Definitely fuel then! Stripping the carbs a third time, showed some crap in the air jet in Number 3 carb looking curiously like foam rubber crumbs. Remembering that the airbox foam seal looked on its last legs, I went through the airbox and intake side with a damp cloth and a vacuum cleaner, hoovering all the crap out between the (new) air filter and the carb intakes. Success! Now running on all four and sounding more like a bike. Running through the rest of the MOT checklist, I got to Fork Seals, and found that the right hand fork seal was oozing grey oily stuff whenever the forks were compressed, and the dust seal looked very rough (gnawed and a bit rusty!!). Just how rough was revealed when I stripped the forks down, the retaining clip holding the oil seal in each fork leg was corroded in place having turned to rust, the fork oil was a horrible shade of worryingly metallic grey. Fortunately new fork seals, proper (Pink?) Fuchs fork oil, and retaining clips restored leak-free operation to the forks. So, having got to the end of my MOT'able checklist, and got it running, I insured it, and put it in for the MOT, which it passed, - the two wheeled paperweight is now back on the road! Having put a couple of hundred miles on it since the MOT, my observations are that the riding position is comfortable around town and on motorway, and it is easy to handle in traffic, allowing feet-up trickling along in Birmingham rush hour traffic. There is no lack of power on the motorway either, with 70mph coming up at around 5000 - 6000 rpm. It seems a bit 'buzzy' though with vibration through the bars making 70mph less of a 'cruising speed' than I would have expected.Do they all do that? I had previously heard that Yamaha 600 Fours had a reputation for being smooth engines . . Based on my previous (Kawasaki) experience, this seems to be unjustified - I would class it as unrefined and a bit rough round the edges, though with decent power on tap. I'm sure I've got a lot to learn yet, - the Clutch / Oil Pump is next on the hit list, as there's also a vibration from that area, I understand that the Oil pump drive gear pin can become worn allowing the gear to move about more than it should . . All advice very welcome on that, or any other vibration related subject. I've vacuum balanced the carbs as well as I can, but the idle (1200 rpm) still sounds more thrashy and tractor like than I think it should. Anyway - Nice to meet you all. I'm in the Birmingham area, so would be happy to meet up with fellow Yamaha fans in the Midlands. Cheers Dave 2 Link to comment Share on other sites More sharing options...
jaimzee Posted August 16, 2015 Share Posted August 16, 2015 Hey Dave - oh mate.. what a fantastic read and may I say your perseverance, commitment & attention to detail is unbelievable..!! Fist in the air when she did start for MOT though and riding down the road - bet that felt fan-tastic..!!!! I think a lot of us would have resigned ourselves to laying that old (girl) 'friend' to rest long ago with the rest of the 'paperweights' in the sky.. But wow, what a story - think you should put a pic on here if you can and let us see her now, in all her glory - (bet she feels great) - bet you both do..!! Well done Dave..Ian Fearnsides Link to comment Share on other sites More sharing options...
slice Posted August 16, 2015 Share Posted August 16, 2015 (edited) Hi Dave, to the YOC, now that's an intro, made me smile anyway, just a suggestion on my 750 pre-divi I found that the "grip puppies" were fantastic at keeping the buzz down on the bike, just a thought but at £12 it's not a lot to make the bike more comfortable. Edited August 16, 2015 by slice Link to comment Share on other sites More sharing options...
blackhat250 Posted August 17, 2015 Share Posted August 17, 2015 Hi dave, top of the class for the essay. great read,, Link to comment Share on other sites More sharing options...
Moderator drewpy Posted August 18, 2015 Moderator Share Posted August 18, 2015 Dave, great read and if you need how to do the clutch, I posted it in the forum somewhere. Uses a pre-BMW mini door pin cut down and re-drill (dead easy compared to what you went through) I thought about getting an Ignitech but the price I have an FZ600 but have fitted the '91 engine, also check the primary gear near the clutch, mine was wobbly loose. there is a vibration around 5 - 6k on these, but its called character Link to comment Share on other sites More sharing options...
meatloaf Posted August 19, 2015 Share Posted August 19, 2015 Greetings, great intro mate Link to comment Share on other sites More sharing options...
GREIGE Posted August 21, 2015 Share Posted August 21, 2015 Welcome !! As an Owner of a '89 XJ600 Paperweight I was interested in all you went through. Mine will hopefully be getting worked on this winter when I get my new "Man Cave" !! ( Ordered & awaiting delivery 6-8 weeks)Also having previously owned a Pre Divi XJ600 I can remember it having a "Buzz" around the 4-6000rpm so I think that it may be part of the character of these particular bikes. Link to comment Share on other sites More sharing options...
mr bignal Posted August 6, 2016 Share Posted August 6, 2016 the xj600 divvy definitely has a buzz at ahout 4,5K revs but the pre divvy should be OK, sometimes, strangely, chain adjustment sorts it otherwise I would say carb balancing, something that i have paid for to be done. Just done over 400 miles on a run, pretty much continuous and no vibe issue to speak of. I do sometimes get pins and needles but that is usually because I've been gripping the throttle too hard. Link to comment Share on other sites More sharing options...
Bigwol Posted October 19, 2016 Author Share Posted October 19, 2016 Carbs now balanced and idle mixture sorted, now well behaved. 1 Link to comment Share on other sites More sharing options...
Sacha Posted October 19, 2016 Share Posted October 19, 2016 Nice one! ...and belated welcome! Link to comment Share on other sites More sharing options...
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