hello new to this site

[zepol]

Whats up am changing out the piston and head on a 83' 200x. Am wondering what else should i replace while am in there? A valve banged a hole in the piston and messed up the head. Why does this happen? Is it easy to change the piston and rings? What special tool do you need? Am new to motorcycles. Barely even know how to ride one. The 2nd day i bought this trike this happend to it. Can someone help me thanks. Also where can i get a good piston and valves? are all pistons the same ? Whats a good price for a piston and valves? how do i know what size piston i need?

[ironslavery]

The valve either got stuck, the valve was out of adjustment, or you have a timing problem. If you did it right you would replace the shaft and bearings while you were in there. Changing out the parts are easy. I am unsure of any special tools needed for disassembly though. Ebay is a good place for parts and you can usually find full piston kits there (search 200x piston kit). I find it to be cheaper than supply stores. The piston size is determined by your cylinder bore. You need to take the top end off and take it to a machinist to get the cylinder measured. You may need to have it bored due to wear or damage caused by your little incident. In this process they shave the cylinder bigger to re round and/or get out scratches. The machinist will tell you how big the piston needs to be. look for ATV/motorcycle engine rebuilding shops they are usually cheaper then a general machinist. My prices quoted here were 65$ racing engine shop for cars, 70$ motorcycle rebuilder, 75$ ATV racing shop, and "a buck 5" general machinist. Welcome to 3 wheeler world. Sorry for your bad luck :(

BTW NOS means new old stock. OEM parts that have been sitting for a long time but never used.

http://www.dansmc.com/pistons.htm

[JasonB]

thats unfortunate, sorry to hear the bike killed itself the second day of ownership! Goodl uck on the rebuild, and being new to motorcycles in general just means you need to ride SLOW! Take it slow, slower than you want to until you have racked up some real hours onthat seat before you try to go tearing around on it. WELCOME!

[zepol]

So i should replace the cam shaft and bearings while am in their? I was thinking this wouldnt be so complex but it seems like it is. Also when i buy the piston does it come with specifications? Also if it seems like the piston didnt mess up the cylinder can i just use the stock size piston?

[350XJEDI]

:Dyes , if the cyl is good mic it then order the piston /rings , dont forget the cam chain , if the cam is damaged change it ,if the lobes are ok then it s probly good ,a light hone on the cyl . good luck:cool:

[zepol]

Why Do i have to change the timing chain?

[zepol]

Is the cam chain and timing chain the same thing?

[ironslavery]

Ok here is what you need to do... Take your top end (minus the head) to a machinist and get it inspected. They will measure the cylinder for out of round or unusual wear It may be more worn in the middle or bottom then the top. the tolerance is in 1/4 of a MM and the naked eye won't notice it. They will tell you If if needs bored or not. While it isn't necessarily required, It would be better in the long run. It will also tell you if the cylinder has been bored before. You wouldn't want to get a stock piston and find out it's too small. they will tell you the story. The stock size piston is 65.0 mm with the next OS (oversize) being 65.25 mm and as you can see the difference in size is minuscule but important. If it needs bored you get it bored. if not you get it honed. you can hone it yourself but I've read where people try to do it themselves and take the cylinder out of round. The cost of the tool itself though would likely cost more then what a shop would charge.


Once that is done you will know what you should do. buy the required parts and while they are on their way clean up your top end and remove the old parts. drain your oil and inspect the oil for metal particle. Go ahead and flush the engine as well from where the top end connects and check for metal particles. repeat until no metal particles remain. A magnet will assist. Now inspect the shaft and bearings following the manual. If it fails the manuals criteria then you should do those parts. It is entirely possible your shaft is worn and could have contributed to the incident from too much vertical play. so if it's loose then you should replace it. If it fails the manuals criteria but doesn't seem that bad just remember the manual is designed for preventative maintenance so that you don't have these kinds of problems.

Ok, now that you have cleaned up the top end and taken the piston off (stuff a rag in the the bottom end when you take the piston off. don't want to drop clips in there.) study what you did and try to understand how it works. Read your manual and learn. It really is easier then it looks. if you become afraid, don't worry. It is all made of metal and you won't break it more than it already is, unless someone gives you a hammer. Everything in there has been lubricated all of it's life and should come apart relatively easy.after you take out the old piston and study the engine Then you can take the rest off. You will have plenty of time to do this since your waiting for parts. Remember to bag the top end hole with some plastic and masking tape when your not working on it though. you can then inspect and decide if you want to replace the rest of the parts.

Now, the timing chain is very important. If it breaks or stretches out it will mess up your timing. This causes valves to open in the wrong part of the cycle. the manual should have a procedure to check the chain for stretching. The cam and timing chain are the same. If it checks good you still need to make sure the chain is timed correctly but I still recommend getting a new chain on a 25 year old bike.


by now you should have a good understanding about how your bike works and lost about 10 hours or so of your life to this project. your new parts should arrive and you can start the rebuild. If you need to bore your cylinder then take the top end and the piston to the machinist so they can do their business. You will put the other parts in while you wait. use new hardware when rebuilding (nuts if possible but not critical, washers, spacers, bearings, gaskets, orings, seals, ect.). Once everything is together reinspect using the book to make sure you do not miss anything. Make sure all the parts are accounted for, new AND used parts. Just because you took it off does not mean it did not end up inside the engine. Once everything is good, go get your block and piston and put all together. Do all your checks again. Inspect timing and make sure the valves operate normally. Replenish oil and start it up. do a warm up cycle and turn it off. Drain the oil and refill and check for metal particles. repeat until oil is clean. do a compression check on your engine and do 2 more warm up cycles 1 more at Idle and another one giving just a little throttle. now go for a light cruise. Enjoy.

I have a lot of information in there about effective preventative maintenance and could be ignored if you do not care. Things such as oil flushing and inspecting parts are not necessarily critical. It will however ensure you don't do this for a long time. I hope you learn from this so that every project in the future is more enjoyable despite the bad experience of having problems in the first place. Read as much as you can and go over the manual until every step makes sense to a modest degree before you dive in. Good luck.