Honda 200cc 4 stroke tuning advise.

[J-roc]

I have a sleeper project on the go, its a mildly tuned atc200m... well the engine anyway. It started last summer when I traded a 1/5th scale gas powered RC buggy for an 83' atc200e. It was a parts bike that I re-assembled with whatever I could find. It turned out to be a bit of a smoker, and well, lest just say it got worse over the summer, lol. I let anyone ride it, no brakes, burning more oil then gas, and no one, not even myself could kill the bugger! It always started, and never quit! Near the end of last summer I finally had a failure, spun the right rear wheel hub on the axle.. no fun driving a trike with only one drive wheel.. I ed a 20g piece of tin between the hub and axle and since then (bout 4 months now) it's been working great.

Anyway, to the engine. I purchased a pair of trikes for $360, both not running. One was complete and only needed the cam pin to spark advancer (pulser) assembly put back in place so it would fire at the right time, ran mint. The other was a rotted old 84' 200m, however, it had a freshly rebuilt engine!

Smoker got a transplant! I've very impressed with the 200m performance, but I want more!

Now, I have a complete top end (cam, rockers, timing chain and top gear, cylinder, piston) from a 88' XR200R and it's in mint shape. Can I just assemble the whole top end onto the 200m block? I also have the 24mm mikuni carb, intake and header too. (I actually have the whole bike, it needed a crank side timing gear and I gave up on it..) Any of that useful on the trike?

This trike as it sits can walk by most late model 4x4 quads, but I want more! It's a beast in the mud, 2 and 3rd gears are insaine mud flinging gears, lol.

Any input is appreciated!

Thanks!

[JustEnough]

If you have not adjusted the valves, change the oil (so you can see the timing marks easier) and then follow the shop manual instructions to adjust the valves. It makes a big difference, improving performance. If it is not running smooth and strong, the carb may need an overhaul too.

It is a utility trike. Maybe you should be shopping for a 350x.

Here is a download source for manuals:

ATC manuals

[J-roc]

I know eh? How sad is that, getting shown up in a mud hole by a lowly 200cc thumper utility trike, ahhaha! If I had high speed internet, I'd upload last summers mud bash video's, it was fun to say the least. I wouldn't dare plunge a 350x into the mud, round here that bike is worth it's weight in gold.. Imposable to get any (good or not) 350x bikes or parts, almost imposable to get anything through the dealerships... I got two atc200s's, a 200m and about two more in parts box's plus the 88' XR200R with what visually looks like identical top end,.. with of course different cam duration and lift. I haven't looked at the XR piston yet to compare to one of the 200m/e pistons I have in front of me but I believe they will interchange..

I want to do this because I can, I have the parts, I have the ability, and I have the tools. Not because I have something to prove. If it turns out good then I will do it all up nice. The frame is rust free, only needs cables for working brakes, new seat cover, repair the tank or find a nicer one that fit's and looks right, mudlites all around, .. it's just something different that no one else has done...

Thanks for the link to all the manuals, that rocks! Now to find a XR200 manual.. cross the parts,.... do some math.... ugh.. work..

Cheers!

Oh, and the valves where set already, they where one of the first few things I checked. To a rule, I check valve adjustment on every 4 stroker I buy, along with change oil/filter and gas if needed, compression and leak down tests. Better safe then sorry. Been there-done that.

[J-roc]

81-84 ATC200 -vs- 88 XR200R
Cam chain, top timing gear and tensioners are same.
Jug, head and piston (complete top end) are different but interchangeable.
Cam's are interchangeable.
Intake, carb and exhaust header are interchangeable.

Now, I looked closer at the XR and all it really needs are the cam tensioners replaced, and now that I know I can fix the XR engine with ATC parts I'm going to,.. I have a new chain and the gears are fine.

Well, at least the info is up, no more guessing what fit's what from an XR200R and an ATC200 engine, regardless if it improves or reduces HP..

Chow!

[Custom200]

It sounds intersting but the big issue would be the semi-auto clutch in those bike, if it woudl be sutiable. A few years back i switched a full xr200 motor into a 200m and that was a fairly big difference from the stock motor. I'd say shop around for an xl/xr motor or even a 200x motor, Still be a sleeper in its own essance.

[J-roc]

I contemplated running a twist throttle, manual clutch XR200 engine in a 200S, but how do I start it? A 200X engine would rock right now, but next to the 350X's, 200X's are the next hardest to get round here.. Loads of 200S-M-E's, 250R's and big reds,,.. but little to no 200X's or 350X's.

I have a yamaha IT400 engine that needs something to do, hehe.

[J-roc]

Ok, how about a 97' DR200 engine? It's electric start! I just got the bike, it's a crash victim, bent frame.. The DR block is longer then a honda. Might be a hard go, gotta pull out the BIG shoehorn to make it fit!

[J-roc]

WOW..... I'm new.. and apparently quite ignorant. I was messing around with the spare XR200R block and some ATC200s engine parts and wouldn't you know it, the 1988 XR200R block IS an atc200s block, it's the same bloody castings (inner), kicker shaft hole in the ATC casting and all! It blew my mind today to say the least, lol.

That means the cylinder-piston-head-cam from the 86'-93' XR200R will bolt on any ATC200(m/e/es/s/x) bottom end, and the difference is the ATC cyl is 192cc with less aggressive cam timing and the XR cyl is 194cc with a more aggressive cam, larger ports (I think), and a larger carb. And THAT means I have my true 200cc thumper sleeper engine just waiting to be built!

Now for some fun, could someone locate info on the boar and stroke on a 88' XR200R bike engine? I believe it's same stroke w/ larger boar but I can't find the spec's.

I love building hybrid engines, even if it's only a little one.

[torker]

This IS really an interesting thread. Please, Can you post the exact specs of all things when you get them figured out?

TORKER.

[J-roc]

Of course, would love to, but all I have to go by is my physical parts and random info from the net.. I need service manual numbers for the XR200R modle years from start to finish, I believe the only oddball XR200R's where made in 84'-85' and they where a 4 valve head, the XR's before and after have the same inner cases and more. I believe the XR crank can be used in the 200s block, look's identical. The friction clutch assemblies are identical. I'm sure there is more interchangeable, but I need the books to reference numbers..... I'm only online using dialup..... I can't take the time to search for this info myself......

oh, btw..

I WANT A 6 SPEED ATC200s!!!!! My 88' XR200R is a 6 speed to top it off, wonder how far off the cases are for a tranny swap... MUHAHAHHAHAAA!!!!

ATC XR200R... XRATC200S.... ATC200SXR, yea.. ATC 200sxr sounds good!

[J-roc]

Here's some basic info I used.

http://100megsfree4.com/honda/h0200/xr200.htm

All the way up to 2002 XR200R uses the 195cc - 2 valve 4 stroke engine.

[J-roc]

1980-84, then mid 84' they changed to a 199cc twin carb (epic fail?) and kept trying in 85', then 1986-1998 and 2002 they continued using this engine:

# Engine: Air cooled, single cylinder four stroke
# Displacement: 195cc
# Bore and stroke: 65.5mm x 57.8mm
# Compression ratio: 10.0:1
# Valve system: SOHC 2-valve
# Carburetion: Single, 24mm (Mine is 27mm? It's physicaly larger then the 200s carb which is 24mm, right?)
# Ignition: CDI
# Starting system: Kick
# Transmission: Close-ratio, 6-speed
# Final drive: Chain

Thing's that make you go hmmm.

Someone please post the ATC200s engine spec's, PLEASE!!! The pdf's are too large for me to download..

[J-roc]

Found it:

ATC200S engine spec's:

Engine: Air cooled, single cylinder four stroke
Displacement: 192cc
Bore and stroke: 65mm x 57.8
Compression ratio: 7.8:1
Valve system: SOHC 2-valve
Carburetion: Single, 22mm (makes sense now, my XR has the 24mm and the ATC has the 22mm... duh.)
Ignition: CDI
Starting system: Pull start
Transmission: 5-speed
Final drive: Chain

So, same stroke, different bore, cool.

[J-roc]

The transmissions will swap! Changed the two gear sets and the shift drum and now have a 6 speed ATC200S engine, hahaha! One down, five up, oh man will that be funny when my buddies try and drive it. I can hear it now: ' Where the hell is second gear on this thing?!?'

Can't wait to try this out, but now I need a good top end for my 6 speed 200S block... but the XR is running soooo good.... damnit! I don't know!?!? Is it worth it.... is it worth it.... .. ... . arrgh.

[J-roc]

Different crank, bearing size and rod but the rod still might work on the 200s crank, need a micrometer to measure the rod end bearing... if it wasn't for the crank bearing size difference I'd try and swap the crank and see if I can use the 200s crank in the XR and do away with the kick start and opt for a pull start dirtbike instead, cuz the XR kickers are junk and are the #1 problem with the bike... press off the bearings, swap cranks, darn, wish I hadda bearing press...

Anyone know the con rod to crank bearing sizes for the 200s and xr200r?