Madison Motorsport Posted March 11, 2009 Share Posted March 11, 2009 I know I'm a little late on this thread, but the 2HW is the FZ600 engine. The 3KM is not an FZ600 engine but an XJ600 engine. The most obvious difference is that the 2HW is water cooled, the 3KM is air cooled. It sounds as though your bike had already suffered from the wrong engine in a transplant. Link to comment Share on other sites More sharing options...
JimR Posted March 12, 2009 Share Posted March 12, 2009 I know I'm a little late on this thread, but the 2HW is the FZ600 engine. The 3KM is not an FZ600 engine but an XJ600 engine. The most obvious difference is that the 2HW is water cooled, the 3KM is air cooled. It sounds as though your bike had already suffered from the wrong engine in a transplant. That is one of the 80's air cooled FZ600 that i mentioned in a pervious post ! Regards Jim Link to comment Share on other sites More sharing options...
nath Posted March 12, 2009 Author Share Posted March 12, 2009 yeah currently i have both engines... the 2HW and the 3KM. so far the only difference ive found is the electrics around the alternator and a slight difference in the case where these are mounted... cheers for the advice jim - ill have a look around before it goes back together - might mean a trip back to yamaha for a pic of them to make sure... oh and massive thanks to J&S Yamaha at Doncaster, always a massive help with any issues - the amount of time ive spent in there trawling through microfiche and parts diagrams! mucho respect! Link to comment Share on other sites More sharing options...
oldtimer Posted March 12, 2009 Share Posted March 12, 2009 That is one of the 80's air cooled FZ600 that i mentioned in a pervious post ! Regards Jim i have an 87 fz600 jim which you so rightly say is air cooled although it confused me when i got it as the local yamaha dealer kept telling me it must be water cooled! well its not,here is the photo of model no hope that clears up any confusion, regards paul Link to comment Share on other sites More sharing options...
JimR Posted March 12, 2009 Share Posted March 12, 2009 i have an 87 fz600 jim which you so rightly say is air cooled although it confused me when i got it as the local yamaha dealer kept telling me it must be water cooled! well its not,here is the photo of model no hope that clears up any confusion, regards paul Hi Paul, you do have an air cooled it must be people who were not around at the time thinking all FZ600's where watercooled as it is beyond what they can remember, with reference to an XJ600 engine in an earlier post this will be correct as the FZ & XJ shared the same motor ... the FZ was just a bit quicker and was in the 'pure sports mode body styling ' as beared out by the FZ750/1000 of the time. Perhaps the 600 (aircooled)was a ploy by Yamaha to get rid of all those air cooled engines they had kicking about (the XJ600 was not a strong seller but it did have some nice clocks to look at). The bike you have was a bit of an 'odd ball' and perhaps Yamaha continued with 2HW prefix for the later FZ600 watercooled motor (I was out of the trade by then) so parts people may not have the parts Fiche from 1987 but have the 1990 fiche which, may also show the same modal type, I cannot comment. But bear in mind you have a bit of an oddball and don't take too much truck from people in the industry that presume they are correct ! Regards Jim Please note this is a general reply & not directed at any user of this site Link to comment Share on other sites More sharing options...
Madison Motorsport Posted March 12, 2009 Share Posted March 12, 2009 The water cooled 2HW was introduced in 1985 The only air cooled FZs I have seen have been 400s and I've had a lot of them pass through my hands over the years. Link to comment Share on other sites More sharing options...
oldtimer Posted March 12, 2009 Share Posted March 12, 2009 The water cooled 2HW was introduced in 1985 The only air cooled FZs I have seen have been 400s and I've had a lot of them pass through my hands over the years. sorry mate but the 86 and 87 fz600 were air cooled the bike i have and its donor are both air cooled as are two more that i know of and have just checked the workshop manual i have, i have a work shop manual which i got by mistake which covers 88 onwards and fzr 600 and they are water cooled. this is my bike and plate Link to comment Share on other sites More sharing options...
JimR Posted March 12, 2009 Share Posted March 12, 2009 The water cooled 2HW was introduced in 1985 The only air cooled FZs I have seen have been 400s and I've had a lot of them pass through my hands over the years. you do talk a load of gonads shall we do the FZ600 air cooled's history ...?oh ok here it is :- way back in 1981 Yamaha produced the XJ550 (528cc a/c four cylinder motor) Within a 4 years the XJ600 was born it took that long as 2 many 550's where sat in my & Mitsul's werehouses .. check the tech bulitins for XJ550's left in their crates to long rusty tanks & green carbs9i ... then we had the xj600 which was an over bored 550 with a different head & carbs (no yics) then there after the birth of the FZ600 air cooled ... I have sent you a picture of the said bike and I would of thought (as you have to be trade) you would have learnt about the bike before you denyed that it exists. Can you confirm that you where in a Yamaha franchise between 1985-1989 guess not ? or else you would know of the machine we talk. Regards Jim Link to comment Share on other sites More sharing options...
JimR Posted March 12, 2009 Share Posted March 12, 2009 Well I never can I see a photo of an air cooled FZ it does look like it ... but they are watercooled arn't they but I must admit the bike is a good example of an air cooled FZ ... I guess it could be water cooled if you added water ... but it could smell funny when it has run for a bit Regards Jim Link to comment Share on other sites More sharing options...
nath Posted March 13, 2009 Author Share Posted March 13, 2009 interestingly my frame has no stamp on it, throwing more uncertainty on the origins of my bike although the fram does have the serial: 2HW-002525 stamped on the steering head... this suggests that the 3KM engine is not the orignal and that it and all the electrics and loom have been bodged in when it was 'restored' - i would love to know who restored it put it that way because they are a moron put bluntly... anyway the deadline is the end of april for it to be back on the road... as im moving house... And both the 2HW and 3KM units i have are definitely air cooled - although the 3KM unit did have a unique lubricaton system using petrol instead of oil BRING ON THE REBUILD!!! oh and nice to see so many FZ600 owners getting involved - i think were somewhat under-represented on here by the R6/R1 mob... Link to comment Share on other sites More sharing options...
Madison Motorsport Posted March 14, 2009 Share Posted March 14, 2009 you do talk a load of gonads shall we do the FZ600 air cooled's history ...?oh ok here it is :- way back in 1981 Yamaha produced the XJ550 (528cc a/c four cylinder motor) Within a 4 years the XJ600 was born it took that long as 2 many 550's where sat in my & Mitsul's werehouses .. check the tech bulitins for XJ550's left in their crates to long rusty tanks & green carbs9i ... then we had the xj600 which was an over bored 550 with a different head & carbs (no yics) then there after the birth of the FZ600 air cooled ... I have sent you a picture of the said bike and I would of thought (as you have to be trade) you would have learnt about the bike before you denyed that it exists. Can you confirm that you where in a Yamaha franchise between 1985-1989 guess not ? or else you would know of the machine we talk. Regards Jim I have, sitting in my workshop, 2 1986 2HW FZ600s, frame numbers 2HW-000103 and 2HW-000116. Both water cooled. I also have a 1986 air cooled FZ400. Also, 2 1988 2HW FZ600s, frame numbers 2HW-002552 and 2HW-002336, again both water cooled. I have never said that air cooled FZ600s do not exist, purely that the 2HW prefix is that of a water cooled, not air cooled, engine - if you wish, I can get Yamaha to confrim this by e-mail. Also, the fact that the OPs bike is a 1988 FZ600 leads me to believe that the 3KM engine is not original as there was no 3KM engine used in the 1988 FZ600. The only possible way to explain the presence of this engine would be that either a) the engine has been previously transplanted, or b ) the bike was actually built prior to August 1986 and had been sat around unregistered for at least 18 months, in which case it is not a 1988 bike at all. Finally, to confirm, I was not Yamaha franchisee myself in the 1980s, I worked for Yamaha - from 1982 until 1993. I started as an apprentice and worked my way up to senior technician in 1987. I now run my own motorsport company in Kent and I have a race team build in progress for Supersport in 2011. Link to comment Share on other sites More sharing options...
oldtimer Posted March 14, 2009 Share Posted March 14, 2009 I have never said that air cooled FZ600s do not exist, purely that the 2HW prefix is that of a water cooled, not air cooled, engine - if you wish, I can get Yamaha to confrim this by e-mail. i for one would be intrested to see confirmation from yamaha because i as have said i have an 87 fz600 and the donor bike that i took fairings off are both 2HW prefix and are both air cooled as is the one owned by my mate all three bikes are original the same engines as from date of manufacture same frames so maybe yamaha built both water cooled and aircooled but that does not explain why the yamaha workshop manual for the years 86 and 87 show the bikes as air cooled but the workshop manual 89 through 93 do show them to be water cooled. if you read the history of the fz600 it says the aircooled fz600 were produced from 1986 to 1988 but were dropped as they were no match for the 16 valve engined competition and replaced by the liquid cooled in 1989 this is in yamahas words. the other differance is the air cooled ones were 2 valves per cyclinder in total 8 valves the water cooled was introduced an at the same time they were built with 4 valves per cyclinder to compete with the CBR,s of the time and other 16 valve engined bikes increasing top speed by 26kmh. if you have a haynes manual it also bears this out i think you will find out that the 2HW prefix continued right through, or so my yamaha dealer tells me. Link to comment Share on other sites More sharing options...
JimR Posted March 14, 2009 Share Posted March 14, 2009 Finally, to confirm, I was not Yamaha franchisee myself in the 1980s, I worked for Yamaha - from 1982 until 1993. I started as an apprentice and worked my way up to senior technician in 1987. I now run my own motorsport company in Kent and I have a race team build in progress for Supersport in 2011. If you worked at Mitsui at that time there is a fair chance we met as I did my Bronze & Gold courses at Mitsui at that time, and my brother was working in the workshop on the road test fleet ( that may have been 1980 cannot remember when he was there), did you work your way up tp senior technician at Yamaha or somewhere else ? If at Mitsui I must have spoke to you on the Dealer Tech desk a few times. Regards Jim Link to comment Share on other sites More sharing options...
nath Posted March 14, 2009 Author Share Posted March 14, 2009 Right im confused... first i can guess that the 3KM is not original with the bike but then i bought a replacement engine which is stamped as a 2HW unit... but that unit is definitely air cooled... Link to comment Share on other sites More sharing options...
JimR Posted March 14, 2009 Share Posted March 14, 2009 Right im confused... first i can guess that the 3KM is not original with the bike but then i bought a replacement engine which is stamped as a 2HW unit... but that unit is definitely air cooled... Dont Worry... I know what you have... 3KM was perhaps an XJ600 motor but as I said the 2 shared the same motor .. the first example of the L/C 600 was when I sold the shop in 88 so it is possible that your bike hung around unregegistered for 12 months so could be an 87 ... but hey its real & I know that bike inside out ! Regards Jim Link to comment Share on other sites More sharing options...
oldtimer Posted March 14, 2009 Share Posted March 14, 2009 Right im confused... first i can guess that the 3KM is not original with the bike but then i bought a replacement engine which is stamped as a 2HW unit... but that unit is definitely air cooled... the 3KM is not original well not to the fz600,Yamaha FZ600. 598cc. 1986 through 1988 were mostly air cooled and did bear the 2HW which stayed with the later models if yours has 2 valves per cylinder then it is air cooled if it has 4 valves per cylinder then its water cooled but anything with yamaha is possible if what i have read is correct they had a lot of XJ 600 engines and the fz was developed out of that the later fz600 were 599cc some bikes built with and aluminium frames then the others were steel now you must be confused, i am sure yamaha do things to confuse us as my mates dragstar has a different rectifier than mine both the same year, good luck with your rebuild, i am going to stop reading anymore about the bloody fz they are right bloody oddballs but i love riding mine it handles well and always gives me a buzz. Link to comment Share on other sites More sharing options...
JimR Posted March 14, 2009 Share Posted March 14, 2009 the 3KM is not original well not to the fz600,Yamaha FZ600. 598cc. 1986 through 1988 were mostly air cooled and did bear the 2HW which stayed with the later models if yours has 2 valves per cylinder then it is air cooled if it has 4 valves per cylinder then its water cooled but anything with yamaha is possible if what i have read is correct they had a lot of XJ 600 engines and the fz was developed out of that the later fz600 were 599cc some bikes built with and aluminium frames then the others were steel now you must be confused, i am sure yamaha do things to confuse us as my mates dragstar has a different rectifier than mine both the same year, good luck with your rebuild, i am going to stop reading anymore about the bloody fz they are right bloody oddballs but i love riding mine it handles well and always gives me a buzz. Too Right had enuff of this unless the is a tech question I can answer ... Regards Jim Link to comment Share on other sites More sharing options...
Madison Motorsport Posted March 14, 2009 Share Posted March 14, 2009 I think the poor guy is confused enough without us bombarding him with the ins and outs of Yamaha's lump sharing scheme Link to comment Share on other sites More sharing options...
nath Posted March 15, 2009 Author Share Posted March 15, 2009 haha no its alright - quite interesting having people who remember when they were new... i was 3 years old when mine was registered!!! people think im mental being 23 yet liking things from the 80s... Frame got cleaned down today and im gonna spray it to get it nice - white i think (any objections) also interesting fact - ive removed the rocker cover from the 2HW engine today and the timing is different from the 3KM... with the 2HW firing something like 1,3,4,2 and the 3km definitely firing 1and4 then 3and2 together... strange sequence i thought... anyway the head will be off the 2HW soon so i can nab the pistons, rings and cylinder then its off to a mates garage for some airline and paraffin cleaning and reassenbly action... Link to comment Share on other sites More sharing options...
nath Posted April 7, 2009 Author Share Posted April 7, 2009 Right then peeps the cases are cleaned to within an inch of their lives, the crank is rebuilt with new big end shells and tightened to 25Nm with my new torque wrench... Question is this... upon inspection i saw that the starter/drive chain guide has snapped into three pieces, with a small section loose in the case miraculously held in place by the two larger sections still bolted to the upper case. Ive ordered a new one from Yamaha (£15) which will hold me up for a few days, is it possible that this is the source of the rattling noise??? also the the chain looks intact with little signs of wear, however according to haynes the chain links should not 'touch' when sat on the bench, whereas this chain does sag in the centre... Ive priced up a new chain (£137+vat), so i laughed heartily and am asking whether its practical to reuse the old one and whether there is a risk of breakage... Quick Edit: can the engine run without the chain guides??? are they crucial to safe engine operation or will it leave slack in the chain??? Link to comment Share on other sites More sharing options...
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