The 2nd hand XR600 Guide / FAQ & Chronology

by John K. - 10/Jul/98

['85 to '87 - 600's]['88 to '90 - 600's]['91 to '98 - 600's][XR6 Chronology ]

This Hints and Tips page, which is based on the Australian released XR's, has been compiled by John K. drawing upon information from Several magazine articles,Technical manuals, Ballards, Personal experience and Information that has been relayed to me by others. If you disagree, have any comments or want to query any of its content Contact JUSTXR.COM

Starting with the 600's because the 500's are getting real old, and the mid 80's seems like a good starting point. I quote Australian Trail and Track, "....previous to the XR600 there were only a few 500 models. We wont bother with them here, as they're pretty ancient and performed only so so in the dirt, were hard to start, and were hot headed... ...as the 250 and 350 of the era?"

"...Dont think they were lemons - the motors were great even by today's standards, but it was too quick for the suspension and handling." T&T

1985 XR600RF, '86-RG, '87-RH

1985 Saw a revamp for Honda's big dual purpose thumper, in order to show up Yamaha's TT600. The main new features included its new larger displacement (591cc) dry sumped engine. Gasses and fuels were handled via twin carb intake to RFVC Head (rotarty four valve combustion) and found their way out through twin headers. With a new frame, suspension (forks and shock), and new looking plastics, the whole package was a notch above the other average thumpers of its day.

 This model is really what handed crown of open class thumpers to the big XR.

Known problems and Disadvantages:

This Model had the 17inch rear wheel which can be, and is getting more so, hard to find decent off road knobbies for.

SECOND GEAR, before buying a bike of '85 to '87 era make sure you test ride it. Shift into and out of second gear many times under varying loads. Take note of how smoothly it shifts and whether there is any unusual mechanical noise. Also pay attention to top gear as well as in some cases it can also be a bit prone to damage and wear.

The electric Speedo, this item is quite trick. I have heard of failure as being a problem, and if you smash one.... well its gonna cost if at all still available. But here are many aftermarket speedo's around these days to replace it.

Other Points to note:

The Rear Drum brake. These drums worked fairly well, but as with most drums they require you to keep them clean. A good dose of water as with most drums renders them pretty ordinary.

The suspension worked pretty well, but chances are the springs may be sagged and need replacing. Also on the list would be fresh oil and possibly seals. If you plan on going quick (and who doesn't) the suspension may need a good going over. So check this out and give it consideration in the overall price.

If the motor is in good condition It should prove to be fast enough for the average rider. Ask the Owner of the bikes history and maintenance, cross your fingers and hope for an honest answer on this one. Listening to the motor can show up poor maintenance. If the bike is generally lacking in maintenance chances are so is the motor.


1988 XR600RJ, '89-RK, '90-RL

1988 was another landmark year for the Mighty XR600. Honda put in a big effort to bury the TT600 which had its last update in '84 at this stage. This revamp ended up a fairly major update. This model Doesn't differ from the current model that greatly. Which means spare parts are still very available and performance parts are still plenty. My Personal opinion is not to buy earlier than an '88 XR600.

The XR now scored a single 38mm KeiHin carb. Which supposedly made starting a breeze. This kinda makes me wonder how damn hard they used to be. It caused a slight sticky spot off idle in many bikes of these models. This problem, the "feel" of the throttle and the flat spot off idle are still with the later models, but it isn't that debilitating. There are also many fixes for it. Ballards sells jets and throttle kits. Another option is the Mikuni Flatslide, if set up right it both feels better and gives the bike more go.

The barrel was updated the the Nicasil type, making the bike run cooler.

It also scored magnesium side cases which were lighter and looked trick with their "gold" finish.

An 18inch rear wheel got the go ahead, and consequently makes tyres easier to obtain for it in this day and age.

Dual stainless header pipes that ran right back to the exhaust looked trick, but limits the choice in aftermarket exhuasts.

The ADR's (Australian Design Rules) put a clamp on this model with an intake restrictor. Chances are however a previous owner has already removed this. I cannot reccomend its removal for road use, but for competition use it would be a must.

With a little work these models can still be competitive today, they have a good strong motor with a good smooth spread of power. The suspension is quite good for enduro work, but suffers in comparison to the later models due to different shock and forks.

Known problems and Disadvantages:

Honda chose to still ride with the rear drum brake. They worked fairly well, but had to be kept clean as previously. I dont mind the drum on my '88 its nice and progressive, will lock up the wheel on both dirt and bitumen, and hasn't caused me any hassles aside from having to adjust it during rides. But two things point to why honda should have updated at this stage. 1/ They are used on all decent bikes now and they wouldn't be if they were no good. 2/ Everyone I've spoken to that has one says,"once you get used to it you will never go back." And thirdly but less importantly it is basically the same as the one on Hondas famous CT125 Agricultural Bike.

ADR Intake Restrictor came into fruition on this model.

Twin Stainless Header pipes can make after market exhausts hard to get and expensive.

New Single Kei Hin carb may need some Jetting and throttle mods, but this is common from these models onwards.

Other Points to note:

The '88 XR600 is in my opinion the earliest one to buy, its not too far removed from the bikes present incarnation and is more than up to most work thrown at it.

I have read in a manual that the '89 onwards xr's had extra seals in the oil pump, but not having heard of any problem that this is a fix for.

These models came out before Honda started hard cost cutting and are supposed to have more power in stock form due to this and the fact that later models were harder hit by the ADR's.

Later model forks and shock can bolt up to this model for an instant hadling upgrade if needed, there is plenty of aftermarket gear available for it also. The 18inch rear wheel makes shopping for tyres much easier.


1991 XR600RM, '92-RN, '93-RP, '94-RR, '95-RS, '96-RT, 97-RV, '98-RW, '99-RX, '00-RY

1991 saw the last real atempt to refine the XR600 as we know it now. It finally scored a rear disc brake. New cartridge forks up front, and a shock more closely related to the one that is found at home in a CR. '91 models are few on the ground, as Honda moved its factory in japan in this year, and production was down because of this. Some cost cutting dropped the motors performance slightly as they went back to steel headers of a different design, the nicasil bore was replaced by a cast one, and the Magnesium sidecovers were replaced with alloy ones. I'm not sure of this but I've been told the head on the '91 onwards 600's may offer slightly less performance in standard form. Changes from '91 onwards were mostly cosmetic in the form of colors and stickers. The few changes apart from these that I know of and have been told of are:

1. Larger Footpegs than previous models (sometime after '89 model, possibly '91)

2. Larger Headlight and higher output stator coil. (sometime after '89 model possibly '91)

3. Larger font axle ('92 model)

The Year 2000 model also included a change to Honda's newer "fighting red" color scheme.


Hondas Big Bore Thumper Chronology

PRE 1983

The first XR's were not readily available in Australia untill 1983. Even though other countries had the XR's since the Late 70's. We had the XL's which were not that different back then from what I can gather. A big rear sprocket, some serious knobbies, a bit of a stripdown to slim the XL, and a set of decent bars was about as close as we could get.

My '79 XL250S was a real old rocket and alot of fun. I got a set of rear shocks off a later model twin shock XL, Rebuilt the top end more times than I can remember untill I got an '81 XL250S topend from base up (with better revised tensioner), a bigger rear sprocket (43 teeth I think?), Put some spacers in the forks to firm them up. Those old 23inch "super hoop" (nickname some people had for them) front wheels were damn hard to find rubber for though but boy they cleared near anything!!


1983 & 1984

This was the first year of Real XR's we had in Australia. The RFVC XR500 with single shock ProLink suspension, front disk brake, about 11inches suspension travel both ends, and dual carbs. Despite the fact the bike was heavy It was a good allround machine for its day.

1985 to 1987

The first year of the mighty XR600. With its new displacement (591cc), dry sump, twin carbs, RFVC head, and twin headers the new XR600 had quite a formidable powerplant for its time. With a quite noticeable difference between this and the previous motors power and torque. This model also scored new looking plastics, new designed frame along with new forks and shock.
The '85 and '86

Engine: 591cc dry sump, RFVC head.

Carburation: Twin carbies, primary and secondary setup.

Exhaust:Twin steel headers into single steel exhaust.

Suspension: New Frame, Forks, and shock redefined the whole package.



 
 

1988

This year was the last major ovehaul the 600 has had to date. This model Doesn't differ from the current model that greatly. Which means spare parts are still very available and performance parts are still plenty. The motor received many improvements. The bore was changed to the nicasil type. Twin carbs were tossed in favour of a single KeiHin carb for better starting and easier tuning. Stainless header pipes were the order of the day. An 18inch rear wheel was selected. The cable type decompressor of the earlier models was tossed in favour of a camshaft actuated system which depended on cam speed.

Engine: 591cc dry sump, RFVC head with cam actuated decompressor.

Carburation: New single 38mm KeiHin carburettor

Exhaust: Two seperate stainless header pipes that run seperate to the exhaust.

I've also been told that the '88 (and probably '89 & '90) ran the same head as the NX650.  This is probably due to the exhaust configuration on these models.



   

1989

This bike was the same as the year before aside from cosmetic changes. I did however find in a Technical manual that the oil pump received a few extra seals. If this was a fix for a problem I'm unaware of it.


1991

This year included a few much needed changes. The rear brake was finally changed to a disc brake. The forks were swapped with cartridge items, and the rear shock was changed to a piggy back style unit more inline with the type used in CR's.
 

1992
Cosmetic changes and larger diameter front axle.
 

1993 to 2000

Little or no changes aside from cosmetic ones.



 
 

Errata - 1998 - 2000

The 1998 to 2000 XR600 didn't change back to a Nicasil bore and stainless headers.  I can't recall where this information came from, but thankyou TT for the correction :)
 


 
 

End of the Line - XR650R was introduced into the XR lineup in 2000 and ran till 2007..

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