I found this document posted here: http://www.3wheelerworld.com/showthr...597#post837597
Seems to be really good info, and the file only had 30 views! Here is a "reprint" of it.
ATC70
1973 - K0 First Gen
The very first ATC70, identified as a 1973 model but probably produced from mid 72 onward. Distinguishing Features: Orange body color, Silver colored forks, 5 hole rear cover plate, Flame design tank decal, angled exhaust silencer, 2 rib foot guards. 7 digit engine number, first two digits 10.ie ATC70E-1000001~
1974 - K1 First Gen
2nd year of the series, production commenced in late 1973 and continued throughout 1974. Leftover stock sold through 75. Similar in design to its predecessor. Distinguishing Features: Red body color, Red forks, 4 hole rear cover, straight exhaust silencer, 3 rib foot guards. 7 digit engine number, first two digits 11, ie ATC70E-1100001~first two digits 11, ie ATC70E-1100001~
1978 - K3 Second Gen
After a long absence the ATC70 returns, why did they stop production of this hot seller for 4 years, who knows. The new design is similar to the ATC90 with one piece rear fender/seat assy, non-laminated steel frame, exhaust system relocated to outside of frame. Outboard brakes meant easier brake servicing. A new improved chain tensioner did away with a splined shaft that was prone to stripping. All in all a nice package with some good improvements.
1979 - Z Second Gen
Second year of the new generation. Very few changes from previous year, slight engine and frame revisions, rocker arm clutch components, transmission parts, brake cam, starter handle. Visible changes restricted to decals. K~ model identification dispensed with (Note: code for this model "Z".)
1980 - A Second Gen
New Model identification begins, if you can count to ten you can figure it out 0=A, 1=B, 2=C and so on. Little or no change from the previous model apart from decal differences and revised camshaft and cam chain tensioner. New engine number sequence derived from Trail Bike models.
1981 - B Second Gen
1981 models changed very little from previous years, basically a decal change to differentiate from earlier models. Paint changes from Light Scarlet to Passion Red although to look at it appears the same color. Gearshift drum revision, basically the same bike as before.
1982 - C Second Gen
1982 models saw the introduction of a 4-speed transmission a welcome revision as the three speed tranny left a lot to be desired. Generally but not always a 4-speed engine could be identified as having 8mm case screws as opposed to previous "Phillips head " screws.
1983 - D Second Gen
Some changes since previous model, cylinder head revision, countershaft, low and second gear revision, throttle cable securing band and guide added, handle bar revision, handle bar mounts get plastic cover, fuel tank revision, exhaust system revision
1984 - E Second Gen
Very little difference from previous model. Hand brake lever revision, exhaust heat shield changes. Tank decal is same design only colors are dark blue and light blue. Seat loses its "Quilted" design in favor of plain vinyl.
1985 - F Second Gen
85 sees end of production for the ATC70 to make way for its 4-wheeled cousin the TRX70. Minor changes limited to decal changes and seat gets new blue coloring. "70" stenciled on seat. revision to cam chain tensioner. Shift pattern changes from all down to all up!
US90
1969-1972 - First Gen
Named the US90 as identified by the engine number prefix of US90. Produced from late 1969 through 1971. Distinguishing features: No headlight or tail-light, Honda name on tank in badge form instead of decal, plastic thumb throttle (prone to breakage and replaced under warranty with alloy unit) 7 digit
ATC90
1973 - K1 First Gen
The first ever ATC90, named the US90 as second model ATC90, some changes from first model, headlight & taillight become standard instead of optional. Seat cover appears to be different, Tank loses badge in favor of stick on decal. Otherwise basically unchanged.
1974 - K2 First Gen
Third model ATC90. US90 engine number now gone in favor of ATC90 prefix. Fold away foot rests replaced with fixed units. Fold away head stock dropped. Front fender changed from metal to plastic, rear fender re-styled. Body color "Orange" borrowed from K0 ATC70
1975 - K3 Second Gen
Introduction of the new "knobby tire" model. Available in any color so long as it was red. Slight frame revisions and inclusion of plastic mud flaps front & rear. Heavier than previous year due to wheel design and accordingly lower power to weight ratio
1976 - K4 Second Gen
Second year of new generation design, very few changes from previous year. Basically the same bike except for decal differences. Honda did a good design job with the previous model and consequently there were no revisions required
1977 - K5 Second Gen
1977 proved to be as unexciting as the previous model in as far as new features were concerned. Very little change from the last model apart from the standard decal changes to make it look different. One interesting point was that a "Chevron" style tire was offered as an option for this model. This tire is similar in design to the ones fitted to
K0~K2 models only it suits the later split rim
1978 - K6 Second Gen
1978 sees the end of production for the ATC90, few changes limited to the tank decals and rear fender decals. Rear carrier rack gets beefed up.
ATC110
1979 - Z First Gen
Introduction of new model ATC110, Not much changed since the previous ATC90 model. Engine gets upgrade to 105cc. Rear fender constructed from "non-repairable" plastic. New decal design, basically the same as last year with a slight performance upgrade.
1980 - A First Gen
Only new decal design. New engine number configuration starting with TB02E~, new model ID system, this model "A"
1981 - B Second Gen
Fuel tank changes shape, Introduction of the much welcome "CDI Ignition". Headlight changes from round to rectangular. Electrical system switches from 6v to 12v.
1982 - C Second Gen
Tank & fender decal changes, seat loses its quilted cover. Headlight switch moves from top of headlight to bar mounted combination switch.
1983 - D Third Gen
Style overhaul, a nice change or an ugly re-vamp depending on which way you look at it. Seat extends further up the tank. Tank shape changes to accommodate new seat design. New look headlight and fenders. Tool box molded into rear fender.
1984 - E Third Gen
84 models saw a few revisions worthy of note, different tank and rear fender decals. Carburetor revision. Rear brake drum and axle changed in favor of ATC185/ATC200 Design. Chain tension is controlled by adjusting rear bearing carrier Redesigned rear carry rack..
1985 - F Third Gen
Last year for the ATC110, no changes for this model except the mandatory decal redesign.
ATC125M
1984 - E First Gen
New model introduced for 1984, basically the same bike as the 84 ATC110 only engine pumped up to 124cc. Nice feature for this model is electric start, however this may contribute to more of these models being scrapped as their engines get transplanted into go-carts and the like.
1985 - F First Gen
No appreciable changes for 85, same bike, different decals, new price sticker
1986 - G Second Gen
1986 models receive whole new engine and frame, old horizontal cylinder design which had been in place since 1970 now replaced with vertical cylinder similar to ATC185. Nice package although some ground clearance may have been sacrificed for new design. New fenders, Fuel Tank, Frame. Basically a whole new bike. When shopping for a 125M this would be the preferred option.
1987 - H Second Gen
No new white plastics for 87 which is unusual for Honda, last of the model line. Very rare model as not many were sold.
ATC185
1980 - A First Gen
Introduction of ATC185, first model to graduate from "pressed steel" to "tubular frame" Nice bike with plenty of horsepower that was lacking in previous models. Separate rear fenders with tool box, this model targeting the "Work Horse" market. 180cc engine, 12v electrical system.
ATC185S
1981 - B First Gen
ATC185 models became the ATC185s in 81, "S" denoting sport, new tank design, 1 piece rear fender, round headlight replaced with rectangular unit, tail light and rear carry rack revised. Brake drum enclosed within cover plate, minor difference in rear axle.
1982 - C First Gen
Few changes worthy of note for 82 models, decompression cable incorporated into pull starter, kill switch goes from top of thumb throttle case to left side combination switch, new design air cleaner & air box, tank and rear fender decals change. Headlight switch moved from top of headlight to bar mounted combination switch
1983 - D First Gen
Last year of production. 83 models get new "Front Suspension" fuel tank shape gets smoothed out, air cleaner and air box get re-designed, rear sprocket gets revised damping arrangement, front & rear rim becomes one-piece, minor changes to front brake panel
ATC200
1981 - B First Gen
Introduction year for new model ATC200, basically an ATC185 with extra cc's added for good measure, seat is removable independent of rear fender. Rear fenders are two piece left and right sided, tool box mounted behind seat.
1982 - C First Gen
Few changes and revisions since last model, decompression cable incorporated into recoil starter, headlight switch moves from top of headlight to bar mounted combination switch, kill switch migrates from top of thumb throttle housing to combination switch.
1983 - D First Gen
Last year of production for ATC200, fuel tank gets smoothed out treatment, air cleaner & air box re-designed, front suspension introduced, minor difference in rear axle, front and rear rims now one-piece, minor revision to front brake panel, hand brake lever shape changes to "dog leg" style.
ATC200E Big Red
1982 - C First Gen
Introduction of new model ATC200E "Big Red" Model aimed at "work horse" market, basically the same as 82 ATC200 only with front and rear fender mounted carry racks, engine has electric start additional to recoil start, sub transmission added to give choice of "high and low" range. Headlight is high mounted with protective guard, ignition panel with key and neutral indicator light mounted on fork top bridge.
1983 - D First Gen
1983 saw little changes for the ATC200E, minor changes to rear axle and sprocket design, hand brake levers change to "Dog Leg Style" , basically the same bike as the previous model with new decals
ATC200ES Big Red
1984 - E Second Gen
Introduction of new model ATC200ES which was basically the ATC200E with the chain driven drive-line replaced with shaft drive. Nice feature included in this model is reverse gear, used ATC200E shoppers should consider this model as the pick of the three as the shaft drive makes for less maintenance and the reverse gear is great for getting out of tight spots.
ATC200M
1984 - E First Gen
Introduction of new model ATC200M, or continuation of old model ATC200 depending on which way you look at it, one piece rims, electric start
1985 - F First Gen
No changes worth mentioning for the '85. last year of manufacture for this model. Same bike as last year, new decals, new price sticker
ATC200S
1984 - E First Gen
New model introduced for 84, design based on old ATC200 specs, has one-piece rear fender with tool box molded in, fuel tank blends in with fender, "S" denotes sports model, one-piece rims
1985 - F First Gen
Few changes worthy of note for '85 models, handlebar mounted combination switch replaced with ATC110 unit, thumb throttle unit from ATC200X
1986 - G First Gen
1986 proved to be even less exciting in the changes department than the previous model. Seat gets blue treatment, that's about it!
ATC200X
1983 - D First Gen
Introduction of new model ATC200X to compliment existing ATC250R, nice package with some good low down torque for the 4-Stroke fans, disc brakes all round, (1-piece) factory alloy rims, tubular fabricated swing-arm
1984 - E First Gen
Very few changes for 84 model ATC200X, swing arm changes from tubular steel to box section
1985 - F First Gen
Same bike as last year besides blue seat with 200x on the side and polished forks with blue fork boots
1986 - G Second Gen
Revamp of ATC200X for 1986, all white fenders body colors, headlamp and tank shrouds remain red, front and rear fenders re-styled, transmission gets an extra 6th gear frame goes from round to square tube construction
1987 - H Second Gen
Last of the ATC200X very rare model, Few changes worth note, tank air scoops get white treatment, just one more year and the headlight could have been made white too!
ATC250ES Big Red
1985 - F Third Gen
Introduction of new model ATC250ES although really just a carry on from 84 ATC200ES with more ccs added. Engine shares a lot of parts with ATC250SX, Fuel tank blends into rear fender, rear side covers independent of rear fender. Kick starter takes over from old pull starter
1986 - G Third Gen
Few changes for 86 model ATC250ES, small modifications to rear brake panel in the form of guards added, modified rear swing arm.
1987 - H Third Gen
Second last year of production for the ATC250ES, was expecting some white body coloring to appear and maybe a blue seat but no. Same bike as last year, new decals new price tag.
1988 "Super Red" - Third Gen
This model was not sold in the USA, but was sold in Australia and the UK. Visual differences include a gray seat and details updated to gray to match.
ATC250R
1981 - B First Gen
Introduction of new model ATC250R, previously unheard of performance features in an ATC model, Swing arm rear suspension with gas charged shock, true front oil damped suspension, race ready 2 stroke engine modified from CR stable. Front disc brakes to slow it down. Really a great package that was well received by the buying public.
1982 - C First Gen
Few changes for the 82 ATC250R, rear drum brake gives way to disc. Brush guard added to alternator cover. Kill switch gets re-located from thumb throttle housing to left bar mounted combination switch
1983 - D Second Gen
Second generation ATC250R, nice restyling job while retaining a lot of the same running gear. Narrower front steer tire, improved suspension travel. Engine gets "black" treatment, new progressive thumb throttle, wheels go from split two piece to one piece. air box redesigned with access from top lid.
1984 - E Second Gen
Last of second generation model. Not many changes here, rear shock arm gets refined. Major changes coming up with next model.
1985 - F Third Gen
Third Generation ATC250R, Water cooled engine, six speed transmission. New plastics design. 85 models have "250R" printed on side of seat
1986 - G Third Gen
Very few changes from previous model, plastics remain the same, some improvements to suspension. 86 models have "ATC" printed on side of seat.
ATC250SX
1985 - F First Gen
Introduction of new model ATC250SX, shares a lot of components with the ATC250ES however is the sportier of the two. Shaft drive 5 speed transmission with reverse gear. Electric and manual starter.
1986 - G First Gen
Some minor changes for 86 year model. Tank gets white treatment and is accented by new design decal. Seat goes from black to blue. Fork boots get blue color treatment also. Rear wheel, brake panel and swing arm revision.
1987 - H First Gen
Last model ATC250SX, few changes worthy of note, tank decal gets more red treatment. New price tag. that's about it!
ATC350X
1985 - F First Gen
Introduction of new model ATC350X. 4-stroke, 4-valve, twin head pipes. 6 speed transmission. seat is blue with "350X" printed on side. Lots of low down torque but not terribly user friendly for hot starts!
1986 - G First Gen
Second model ATC350X, few changes from last model, front and rear fenders go from red to white, revision to front brake caliper. Seat has "ATC" printed on side.
Reply With Quote
If it listed every single difference in every model along the way, the first post would be 3 thread pages long! LOL!
Originally Posted by ride-red 250r
