200s head on 185s cylinder

[Truck Norris]

I broke one of the exhaust studs off on my 185s. I have a parts trike that is a 200s. Im wondering if i could just swap the head over or if id have to swap the cylinder too. I want to do as little wrenching as possible so im hoping i can just put the 200s head on. Thanks for any help.

[Dave8338]

It is a direct swap over. No need to change anything else.

[Truck Norris]

Sweet thats what i wanted to hear! Should i use a 200s head gasket or a 185s gasket. It will be a 200s head on a 185s cylinder

[prometheus]

I believe they are the same gasket set.

[Dave8338]

As mentioned, same gaskets. While you're in there, I would suggest replacing the valve stem seals, too.

[Truck Norris]

From what i found the part numbers on the oem diagrams are different for the head gaskets but the aftermarket gasket sets are the same. Something like this should have that valve seal included right? http://pages.ebay.com/link/?nav=item.view&alt=web&id=291091630927

[Dave8338]

According to what the seller states below the picture, they should be in that "kit". They are not in the picture, however. Nor is that a gasket set (in the photo) for either a 185 or a 200. Picture is only for reference and a poor reference at that.

[Truck Norris]

Maybe this one? http://pages.ebay.com/link/?nav=item.view&alt=web&id=400840320403

[Scootertrash]

If you want to do as little wrenching as possible, why are you taking the head off of 2 motors instead of one? Take the head off of the 185, have the stud removed and put it back together. Why crack open a motor if you don't have too?

As far as gaskets you don't need a full gasket set just a top end:
Go with Cometic and be done with it.

http://www.ebay.com/itm/Cometic-Top-End-Gasket-Kit-67mm-Fits-Honda-ATC200S-1985-1986-/391073903176?pt=Motorcycles_Parts_Accessories&hash=item5b0dd23248&vxp=mtr

ETA: This ones a bit cheaper:

http://www.ebay.com/itm/Cometic-C7025-Cometic-Top-End-Kit-67mm-Bore-Honda-/311078344455

[Dave8338]

Myself, I would go this route. http://www.ebay.com/itm/TOP-END-GASKET-SET-HONDA-ATC185-ATC200-ATC200X-ATC200S-TRX200-ATC200M-ATC-200-/381035893732?pt=Motors_ATV_Parts_Accessories&hash=item58b78253e4&vxp=mtr

Save yourself some money. You're working on stock compression (9:1)

Just my .02

[Truck Norris]

If you want to do as little wrenching as possible, why are you taking the head off of 2 motors instead of one? Take the head off of the 185, have the stud removed and put it back together. Why crack open a motor if you don't have too?

As far as gaskets you don't need a full gasket set just a top end:
Go with Cometic and be done with it.

http://www.ebay.com/itm/Cometic-Top-End-Gasket-Kit-67mm-Fits-Honda-ATC200S-1985-1986-/391073903176?pt=Motorcycles_Parts_Accessories&hash=item5b0dd23248&vxp=mtr

ETA: This ones a bit cheaper:

http://www.ebay.com/itm/Cometic-C7025-Cometic-Top-End-Kit-67mm-Bore-Honda-/311078344455

I dont want to spend the money to have the stud removed and put in when i could just swap them for free.

[Scootertrash]

How much of the stud is left sticking out of the head?

My local shop charges 20.00 for stud removal

[Scootertrash]

Myself, I would go this route. http://www.ebay.com/itm/TOP-END-GASKET-SET-HONDA-ATC185-ATC200-ATC200X-ATC200S-TRX200-ATC200M-ATC-200-/381035893732?pt=Motors_ATV_Parts_Accessories&hash=item58b78253e4&vxp=mtr

Save yourself some money. You're working on stock compression (9:1)

Just my .02

No offense intended, but Cometic gaskets are manufactured in the USA on US soil, not made in some other country and sold here as "Made in the USA".

They're excellent gaskets and support OUR economy. Win/win ;)

[Truck Norris]

Theres actually alot left sticking out. Im goin to try and get it out myself. My old man has some sockets made to pull out broken studs. He has some crazy pliers that tighten as you turn them too.
What im wonering is if it comes out how do i get a new one in? Or could i use a bolt maybe?

[Scootertrash]

The stud threads into the head like a regular bolt.

This is what an exhaust stud looks like. These aren't for the 185, just a random google image:

212192

Soak the stud in some type of thread lubricant, I prefer Kroil. If you have the head off try to stand it up so the lube can work it's way down the threads. Let it soak for a day, reapply then let it soak another day. Be patient and go easy. You can also apply heat with Mapp gas or and oxyacetylene torch, propane won't heat that head size chunk of aluminum very well.

Sometimes if you try to tighten it just a touch it will help to break the threads loose. I know it sounds nuts, but it does work. You just want to tweak it a bit, not try to get a full or even half turn out of it.

If you were up here I'd have you swing by and I'd try to help ya out.

Remember patience is the key. And maybe a swear word or two :naughty: :lol:

When (if?) you get it out you can use regular bolts if you wish, just make sure they aren't too long. ;)

[Truck Norris]

The stud came out no problem. Replaced it with an allen bolt and it worked great. Now ive just gotta figure out what to use for a straight pipe. Open header until then:naughty:

[Scootertrash]

Straight pipe as in no muffler? Not trying to rain on your parade, but you do know that noise does not equal power, right?

[Jmoozy27]

Anything is better than nothing. Go to a tractor supply or muffler shop and get something made. Other wise it will run like crap and possibly ruin your motor. And melt anything within a foot of that hot asss header. Just sayin....

[oscarmayer]

you may consider running a XR200 cam as it will give a little more getup and go. but everything is swapable. the valves are the exact same size as well.

[Truck Norris]

Straight pipe as in no muffler? Not trying to rain on your parade, but you do know that noise does not equal power, right?

Ive heard a straight pipe and modding the air box for more air and then jetting acordingley will add some power.

[Jmoozy27]

The trick is getting the jetting right. But you also want to transfer the heat away from the motor, especially with an air cooled motor. They were designed with a full exhaust for a reason. If you do run a straight pipe, it may be a good idea to run a custom one that at least goes to the back of the machine and gets it away from the plastic.

[Scootertrash]

Your motor needs some back pressure to run right, that's another task of the muffler. Not just quieting it down.

You dial in your carb after you've installed your exhaust and modded your airbox and installed the filter you've decided to use.

My 84 200S hasa Wiseco 10.25:1 piston, an XR200 cam, intake, and carb, I did a light port and polish (removed and smoothed all the casting imperfections out of the intake port, 80 grit finish. Same with the exhaust port, but a nice not quite mirror polish.) Matched up the intake manifold with the head and the manifold with the carb and aligned them both when they were installed. I run a Uni foam filter with a stock airbox since we hit water quite a bit and I don't want to be sucking water into the carb ;). I run a DG exhaust, not the best but I bought it before I knew. Been eyeing up a SuperTrapp universal muffler that may take some modding to fit, but they are adjustable with the disc set up so that's a plus. As it is right now it winds out quite nicely. I leave any buddies or neighbors stock 185/200 in the dust. ;)

The SuperTrapp will have to wait tho. My 85 Low Rider is in the process of getting a facelift/remake, our 78 Shovelhead FLH that needs some lovin, and the wifes Road King has some upgrades planned. Sooo many toys, sooo little moneey.

[thcowboy]

You will burn the exhaust valve into the head if ya dont have backpressure

[Truck Norris]

4 stroke engines requiring Back pressure is a myth

[Jmoozy27]

Old wives tail??? Huh???

[Scootertrash]

4 stroke engines requiring Back pressure is a myth

Alright, I'll play.

It's not really called "back pressure", it's called "scavenging".

On a 4 stroke you want the pipe large enough to allow the exhaust gases to easily escape, but no so large that the gases escape with too low of velocity. The exhaust velocity is important so that the momentum from the moving gases will leave a negative pressure wave (basically a vacuum) behind each pulse. When an exhaust is tuned for a specific engine and RPM range, then this negative pressure wave will be at a peak at the exhaust valve when it opens the next time, creating a larger pressure difference between the combustion chamber and the exhaust port. This pulls the gases in the combustion chamber out, and helps pull the fresh charge of intake air/fuel in (this is why there is valve overlap). This is called scavenging. Beyond that, minimizing restrictions such as tight turns or decreases in pipe diameter are key to keeping flow up.

The bolded part is where people get the term "back pressure"

So unless you are going to spend the time designing, modifying and dyno testing to get your straight pipe the optimum diameter and length for your motor with the bends you need to have it fit the bike properly, you will be making a lot of noise with a minimal improvement over stock. It might sound like you're making tons more power but there isn't going to be that much difference.

Drag pipes (straight pipes) are called drag pipes for a reason: They perform best at high RPM/wide open throttle. All those open headers on drag cars? Yup, tuned for length and diameter for best performance out of that particular motor. They don't just slap a set of JEGS headers on and go to the strip.

Most importantly, Nevada requires a USFS approved spark arrester if you ride in/on State Parks and trails (which includes trails on road right-of-ways ;)). Your straight pipe will be loud and attract attention, not all of it will be good. A ticket for an unsilenced pipe and/or no spark arrester will cost you a good chunk if not the same as a nice free flowing muffler. Along with that you stand a chance of pissing off neighbors and other citizens who may not appreciate the noise.

Horsepower costs money, you are only going to squeeze so much out of your stock motor until you open the valves more and longer. Your stock engine will only allow so much air and fuel into the cylinder no matter how much you open the airbox, there's no way around it.

[Jmoozy27]

Alright, I'll play.

It's not really called "back pressure", it's called "scavenging".

On a 4 stroke you want the pipe large enough to allow the exhaust gases to easily escape, but no so large that the gases escape with too low of velocity. The exhaust velocity is important so that the momentum from the moving gases will leave a negative pressure wave (basically a vacuum) behind each pulse. When an exhaust is tuned for a specific engine and RPM range, then this negative pressure wave will be at a peak at the exhaust valve when it opens the next time, creating a larger pressure difference between the combustion chamber and the exhaust port. This pulls the gases in the combustion chamber out, and helps pull the fresh charge of intake air/fuel in (this is why there is valve overlap). This is called scavenging. Beyond that, minimizing restrictions such as tight turns or decreases in pipe diameter are key to keeping flow up.

The bolded part is where people get the term "back pressure"

So unless you are going to spend the time designing, modifying and dyno testing to get your straight pipe the optimum diameter and length for your motor with the bends you need to have it fit the bike properly, you will be making a lot of noise with a minimal improvement over stock. It might sound like you're making tons more power but there isn't going to be that much difference.

Drag pipes (straight pipes) are called drag pipes for a reason: They perform best at high RPM/wide open throttle. All those open headers on drag cars? Yup, tuned for length and diameter for best performance out of that particular motor. They don't just slap a set of JEGS headers on and go to the strip.

Most importantly, Nevada requires a USFS approved spark arrester if you ride in/on State Parks and trails (which includes trails on road right-of-ways ;)). Your straight pipe will be loud and attract attention, not all of it will be good. A ticket for an unsilenced pipe and/or no spark arrester will cost you a good chunk if not the same as a nice free flowing muffler. Along with that you stand a chance of pissing off neighbors and other citizens who may not appreciate the noise.

Horsepower costs money, you are only going to squeeze so much out of your stock motor until you open the valves more and longer. Your stock engine will only allow so much air and fuel into the cylinder no matter how much you open the airbox, there's no way around it.

Some of you guys define your thoughts with words so well. Everything that you just said was spinning around in my head with no chance of making it into a post. If it would have, surely it would look like this: "Don't be a Dumbasss, Just buy a DG and be done with it" Im glad you posted before I did, yours made more since and is accepted by members much better....

[Scootertrash]

Well, DG isn't a bad pipe, but they also don't have a spark arrester. I have DG on my 84 200S, but I've looked into fitting a SuperTrapp end cap to it so I have a spark arrester when I'm on the trails or road side. I've never run a Cobra, But from what I've heard they are obnoxious sounding pipes. I think Cobras have a spark arrester, butif you plan on running one, I would verify thru Cobra first.

My opinion is that while kind of spendy, Supertrapp mufflers are great quality, repackable and adjustable with the disc system they have, and the disc system is an approved USFS spark arrester. You couldn't ask for more in an exhaust system. The old saying rings true: You get what you pay for.

[oscarmayer]

truck, your actually pretty wrong. as mentioned unless your running WOT non-stop and plug the pipe right after a run, you will crack a valve from cold hitting the valve surface. seen it many times on a drag car, and those were tuned specific for the car. 4-strokes do require some type of way to hold the pressure after the run they also need some backpressure to properly run at lower speeds and produce proper torque. that is where it comes from , similar to a 2-stroke but on a much simpler scale, requiring the motor to push out the gas slightly increases the torque aspect on a given motor. but again this is to a specific degree. I have taken and tunes many 4-strokes. from cars to quads/trike motors the best example was my son racing 70cc 4-stroeks. they produces 12-13hp and ran about 9-10k RPM. one time the muffler fell off and unless he went WOT the bike motor would not run. it was hard to start and had a ton of power loss anywhere but WOT. This the muffler tunes the back pressure it needs to perform. this is probably the "scavenging effect" discussed but IO still refer it to backpressure as on a single cylinder, there is no cross pipe to connect for the true scavenging.

Hope this helps you guys out.