Orville538

13 hours ago, SlammedRanger said:

Just a heads up also bud. Its a trx300ex. That is the proper name for it. Or a fourtrax 300ex.  Not to be confused with the trx300. Or fourtrax300 which are utility quads. The best way to tell the difference is sport quad 300ex is manual clutch drive. The 300 utility quads are semi auto.

You say this correct? TRX EX300  I look at everything and ask questions to the sellers before purchasing parts,Thank you very much Slammed & Fish again!!! Fish you reminded me of someone who I grew up with and he is like my brother but from another mother,he called me Orv' for shorts all the time... Many blessings to you both and your families!!!! Pictures will be posted as soon as I can gather the parts...I'm not buying nothing Chinese either knock off's crap!!

Just now, Orville538 said:

Hey Fish and Slammed I didn't notice some I should have,the piston only had 4 rings it was missing the darker color ring that does in the center of the piston you know in between the top and the 3 bottom ones (the 2 skinny ones and the wavy one that goes in the center of the skinny ones) well that one was missing for sure because I didn't take it out at all.... Now  How was that even working/running? Thats obviously not good? What a hack that guy!!!! 

I will post all the pictures of all the work I do to the TXR EX300,bare with me because I'm buying parts little by little,next I'm buying the 300cc head kit wiseco piston,the Hotcams stage 1 with new sprocket,already bought rocker arms waiting on delivery....

On 1/16/2020 at 8:47 AM, Fishfiles said:

Orv' , I was over at the other  site where you posted about your piston ID , there are 2 post and one was yours ----- hope you stick around and take up thru the rebuild process and the final outcome 

Hey Fish and Slammed I didn't notice some I should have,the piston only had 4 rings it was missing the darker color ring that does in the center of the piston you know in between the top and the 3 bottom ones (the 2 skinny ones and the wavy one that goes in the center of the skinny ones) well that one was missing for sure because I didn't take it out at all.... Now  How was that even working/running? Thats obviously not good? What a hack that guy!!!! 

9 hours ago, F250 guy said:

Lot of work to do there. 

Yeah Im just gonna do this...I really don't care for the BBK this atv my son is gonna ride it anyway,I'm building me a 01 Raptor660r with all Hotcams Top end stuff,Hinson clutch basket and pressure plate,gytr clutch,and so on.... but back to the Honda subject I'll just get this 300cc kit,I ordered the rocker arms last night "Honda brand" not cheap crap...but I want to THANK YOU SLAMMED & FISH for you dedicated help...you guys are awesome!!!! All this is for my boy.... Isee that any 330cc kit  cases need machining....

8 minutes ago, SlammedRanger said:

Good lord my man. That is some crazy amounts of banjo tuning skills that guy had. Here are your options. If your dead set on the 330 you will have to mill the cases. I think i know what they did now. They purchased a 330cc kit from niche. Hacked it into the cases and called it a day. If i was in your shoes. I would go back to stock bore or do a smaller over bore and redo all of it. Sadly thats kinda the only option here. That sleeve is scrap metal. Piston isnt much better. Good thing is you can probably save the cylinder head atleast.

This are oem replacement supposedly no cases dont need machining or I saw a honda brand jug made into a 330cc jug for $120-$130 o e of the 2 and I'm gonna need those rockers and camshaft as well

3 minutes ago, SlammedRanger said:

Oh man those rockers are toast. And that sleeve is way to thin to bore anymore. Also your saying the piston is 90mm? I thought the first few photos said it was 79.4mm? Im 

Interesting you're right,i took measurements from bottom and today from the top 2 different measurements and I knew the rockers were no good as soon as I saw them and felt them

11 hours ago, Fishfiles said:

Hope you not mad about me high jacking your thread either. Always think the more traffic the better.  Sometimes it takes someone to say something stupid for another to think of and say something smart —- I am full of stupid 
 

I think I would start over.  Would be a bummer to sink mo money into it something that you are not even sure what it is and have it fail again.  

Look at this I think is this an OEM cylinder head....this is the hack job someone did....

6 hours ago, SlammedRanger said:

300ex's do tick. But not super loud. Your tick was almost certainly the cam and rocker arms are worn out. Most likely they were adjusted wrong aswell. You have to readjust the valve lash anytime the valve cover comes off. Since the rocker arms are in the valve cover and the thickness of sealer will very. Rod side to side play isnt a big concern. But any up and down play is bad news. And in all honesty the sealer is what is used for the valve cover on a 300ex. No gasket. Which i always thought was crazy. Alot of atvs dont use gaskets for the case halves either. Just hondabond. Or yamabond or what have you. I personally like gaskets. I always spray both sides with copper spray for good measure.

Hey Slammed This is the bottom sleeve grinded down more piston pictures and the 

6 hours ago, SlammedRanger said:

300ex's do tick. But not super loud. Rod side to side play isnt a big concern. But any up and down play is bad news. And in all honesty the sealer is what is used for the valve cover on a 300ex. No gasket. Which i always thought was crazy. Alot of atvs dont use gaskets for the case halves either. Just hondabond. Or yamabond or what have you. I personally like gaskets. I always spray both sides with copper spray for good measure.

Hey Slammed here the pictures of the grinded down sleeve with measurements some are a millimeter thicker or thinner,piston is 90.0mm cylinder 90.5 mm head gasket 80.0mm....also some pictures of the camshaft rocker arms which feel sharp as a knife on the edges I don't think they are good anymore and the little screws for adjustment in between the valve and the bolt....

14 hours ago, toodeep said:

Welcome to the forum.  You have a 300EX correct? ( If so we can move this into the sport section that needs more threads.) I would have to dig up specs and research to help out. Piston pin size is the first step when trying to figure out backyard big bores. Once you know which motorcycles and atvs use that piston size then the real search begins. I'll need to be on the computer for that to make it easier for me and right now I'm mobile. 

 

The condition of the parts, do you need the big bore? Possibly you could find a used top end and start from scratch and know exactly what you have. 

If you can move the thread go ahead.... I just don't want to loose the help please....

14 hours ago, SlammedRanger said:

If someone put a 350 rancher piston in there i would be very shocked. You would have to do extensive measuring and clay it and measure again. The chances that all the valve pockets would line up and everything would just work would be extremely slim. Niche is a kind of generic brand. They dont really make things with tight tolerances and doing a custom build with there piston would be something i would be very skepetical of. I would be measuring the thickness of the sleeve down at the bottom and see if going to a 80mm 330cc bore would be feesable. That would be easy for alot of reasons. But if the sleeve is to thin you are in a situation. I would probably at that point get a niche cheap kit with a cylinder-piston and gaskets and go back to a smaller bore to not have to mess with case milling. My .02

Hey Slammed I forgot a major detail this honda would tick tick tick loud....and this came from a trade I did...long story short the guy who sold this to the guy I made the trade with told me that the guy told him "I just rebuilt this engine and is ready to rip" and the ticking on it is normal on this Honda's!!!! All this is coming from the original owner.... anyway when I heard it and saw the grey gaske goo coming from the valve cover and missing bolts and bolts loose I knew right away that it was a hack job....and the cherry on the top was I noticed the bottom of the sleeve shaved down all around.... and the rod has alot of play if I wiggled it side to side....I will post pictures when I come home later on,I'm at work now.... I do new construction homes in Fl.

18 minutes ago, SlammedRanger said:

I have not. I did some research on them at one point. Never found anything that really sold me on the idea. And my custom pistons came with rings so im just gunna run them. Sorry OP were kinda hijacking this thread.

No biggie slammed,I appreciate the help also Fish I want to thank you for your time and info as well,I don't like wasting no ones time because time is valuable you cant give time back to no one,BTW as yoy guys know I'm new to this forum!!!! I have some knowledge about atvs but not to your level,with that said I researched Wiseco they have a 79.50 mm 8 8:1 but is for 350cc rancher? and a 78.50mm 8 8:1 

I got this Honda TXR EX300 but I suspect it has a big bore that someone made fit without machining the cases...apparently the person grinded down the cylinder bottom sleeve and fit the cylinder head somehow,I will post pictures of the sleeve tomorrow possibly,for now I have this and need help whti the size of piston needed,looks like the camshaft is a bit rough to...maybe? Piston skirt has this scratches...piston is Niche brand like cylinder head sold @ Ebay or Amazon