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2012 RMZ 250 engine noise and hard start

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My bikes been hard to start and making a ticking noise in the top end after a new piston and crank. 

Just removed valves and nothing broken or bent a lot of carbon build up on the exhausts especially though (I guess this is normal?)

Some cam journal wear = some scoring marks nothing's crazy and a minor bent c clamp is my only guess... piston didn't look like the valves were beating it but I dunno ...

Here's the noise

Cam journal wear

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Bent c clamp

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Edited by RMZ2Fifty

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who did the rebuild ?

did you check the valve clearances ?

check you cam chain tensioner is working properly

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A buddy who works for a reputable shop. Valve clearances are in spec. Cam chain tensioner is always snug. I've ripped this thing apart more time than I've wanted too chasing this ticking noise and hard start, so I'm pretty keen to Tdc proper timing and valve clearances, but none seem to be causing this tick. The only signs of excessive wear is in pictures on cam journal slight scores on cam shaft and bent c clip, and from my knowledge engine noise comes from metal on metal contact.

I'm gonna upload pics of piston and valves and see what y'all think but is it possible the wear on those parts could cause that noise?? Shit sound loud and no bueno and seems to be getting louder. Originally sounded like right side intake valve now it sound throughout top end and stethoscope to exhaust ticking got louder. Any help homies would be appreciated 

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On another note, I hadn't noticed the gouge in the valve port until I took picture possibly the bucket is getting caught up as it slides up and down?? Buckets have been extremely hard to remove as well... I know micrometer to thoroughly inspect valve stem conditions, I have to pick up a new one but from visual inspect they don't seem to bad just a little carbon on them. Not much play in there seats either. 

As for cam chain itself I noticed left to right play on cam sprockets this normal??

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On another note, I hadn't noticed the gouge in the valve port until I took picture possibly the bucket is getting caught up as it slides up and down?? Buckets have been extremely hard to remove as well... I know micrometer to thoroughly inspect valve stem conditions, I have to pick up a new one but from visual inspect they don't seem to bad just a little carbon on them. Not much play in there seats either. 
As for cam chain itself I noticed left to right play on cam sprockets this normal??

Did the shop start it after the rebuild or were you the first one to start it

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No I did. Rebuilt because of "Rod Knock" ended up being a chipped tooth off clutch basket primary gear, which I replaced. But in that mess I was searching for alternatives he told me about chipped tooth but I spent all that money on parts that need not replacing I was a bit pissed at him and decided id be doing the work on out. While tearing down engine myself one of the valve cover bolts interior threads got stripped and wouldn't secure the cover. Tried retapping the threads same size, started her up she sounded great but threads didn't hold. Oil was leaking from valve cover. Somewhere in this point my lack of knowledge MUST (like definitely)  have &%$#@!ed up the timing removing the cam cap to re tap it. I remember removing the cam cap and intake cam moved and saying &%$#@! I didn't wanna move anything!! I didn't ride the bike this way, I eventually got schooled by a homey on TDC and timing and thought I did it correctly (went off screwdriver and piston, not actual TDC from fly wheel. Could have been 180 out) and bike started and ran fine. But soon bike started to degress to this point.

Edited by RMZ2Fifty

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I wrote a speel and deleted it here's the better question who's the actual shop mechanic and as I may have to bring it to someone of rank to fix this. 

Youve heard what I've explained as the issue and please ask for details if you have to but I'll give a hundred dollars to whoevers suggestion fixes this problem first... even a non mechanic if they're right first. 

If I brought this bike to your shop how would you figure this out?? Name the steps and I'll do everyone. If we're talking mic ever little machining part well lay it out, I'll walk every line. 

Shops charge buckoo bucks for jobs they schedule only for a few hours. It's been days for me and I wanna ride but you don't bring your girlfriend to a cock party when you wanna &%$#@! her right? Catch my drift? You've seen the pics you've heard the story having the bike in front of you wouldn't change much but taking up garage space. 

Tell me everything you would do if it was on your desk. And you have my scout honor Benjamin franklins big head gonna Chris Benoit in ya pocket!!!

Edited by RMZ2Fifty

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Damn howd that bend? Cause it wasnt set in its groove right. Then when it was bokted down thats what tweaked it. Set it on glass. How wobbly is it? And the cam area looks like no oil, grease, moly, nada was put on that bone dry head for startup after rebuild. So then a not sitting flat cap was letting the cam bounce around not straight, causing those scuffs. I wouldn't trip in those. The cam caps your main concern. Your valves are fine. But specs on the scuffed cam, redo. If they were calculated with the wobble gap. But seating sounds fine. Sorry i was MIA. But this reputable shop...you got paperwork on work done? Cause any semi expert will see what I saw. If that clip was any furthur out itd be mangled and cause a heap more trouble.  Go to the boss and talk it out like an expert not an ahole. Be like I came to you guys to get the job done rights..and now I got more work/parts to get? Bad business. Cause YOU know how to install a cam...thats a careless overlook. 

PM me

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Yea he did it outside the shop so not much I can do, besides I don't think he &%$#@!ed it up but yea I'm not sure seeing as cams may not of been lubed. How'd the c clamp got bent i have no clue, but how likely is it that it's the c clamp or scuffed cam caps? It sounds like a jackhammer inside the top end, do the journals need to be machined? Could the cams have been damaged and that's the noise??

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Here's pics of the valves after I cleaned most the carbon off..

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id say they look fine, but could one possibly still be bent? My bullshit mic at least told me they're the same diameter through out the stem. As for length slight different from ex and intake but that's what shims are for yo fill that difference correct?

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I spoke with my brother who is a tech a MMI, he and another tech watched your video and inspected your photos..they want to know how the crown of the Piston looks? They also said that the valves may not show signs of wear because they are hardened steel. Next, they really think that something may be going on with your timing chain and tensioner

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Crown of piston looks good Cam lobes I'd say look fine, as for tensioner working properly when removing valve cover chain seems tight not sure what else I could do to verify it's working. As for the chain being worn doesn't look so but not sure I know what is good or bad for a timing chain

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Crown of piston looks good Cam lobes I'd say look fine, as for tensioner working properly when removing valve cover chain seems tight not sure what else I could do to verify it's working. As for the chain being worn doesn't look so but not sure I know what is good or bad for a timing chain

Look on the side walls of your cylinder and see if the chain has been slapping the chain guide or actual cylinder wall
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On 7/3/2017 at 3:46 PM, slowgs2001 said:


Look on the side walls of your cylinder and see if the chain has been slapping the chain guide or actual cylinder wall

I'm not quite sure I get this. If we're talking cylinder walls the piston slides through everything looks fine even re installed the rings correctly and compression is great but no marks in there not sure I'm understanding you correctly cause the gain wouldn't hit there. I had the head off and all looked fine on the walls the chain guides would be hitting. Guides looked fine to no excessive wear well lubercated and all. Chain is tight but my dad said possibly chain tension is good but the tensioner and spring assembly might not can I test this somehow with out buying a manual one? 

Also I have some pictures of the decomp spring and c ring retainer clip which the intake c clip was bent tried to straighten it out best I could but not much luck.. could one of these be the issue?

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You should A-just order a brand new one and feel confident your stuff is at 100%. And B-heat with blowtorch or on stove or in oven. And pull apart on both ends with needle nose. The "smile" of that half circle needs to widen. Its "smile" has tightened. To me it looks like thats why its sticking out...were both rings the same size in there? Get a new one though. I would just experiment until my new ine arrived. I dont like the look of the clip either but how that would be a clicking, I couldn't tell you. Unless its in the balls of the bearing but not likely 

Get a new one regardless 

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So to keep anyone in the loop, as I'm not positive this is not a valve train issue as it may be an oil pump issue. I think those are both the same. My last idle of this bike for tops 15 minutes has resulted in a new outcome on the cylinder head. I have always heard this noise but never found metal shavings of steel in the cylinder head specifically in/on/around left intake cam side. I removed filter minimal spec of shaving convincing me no oil circulation to top end causing cam to function a little brut or more so. My further destruction of this has yet to be found and as shaving wrrr secluded to one camshaft lobe and bucket I am not yet sure if a bearing has failed(steel?) or the lobe is catching on cylinder head block which is aluminum so I can't see that being the case. Lobe is rigid on its outer face slow motion has it pretty close to the valve bore of cylinder. I am assuming this intake got cam has somehow been warped to malfunction. Cam journals may look worse as well as lube still being red as it has not been flushed by oil. I'm going to remove flywheel cover and such and determine the health of the oil pump. Hoping no other damage has been done but at least I got what I asked for to remove the cover and see the damage something I haven't been able to do hopefully this is not an added problem. Before this I had thoughts of detonation to be cause of noise slowgs broke it down how that wouldn't lead to this and I think he made his point. My tps is malfunctioned and being replaced. I am starting from the bottom like drake in a McDonald's. Gonna work from there making sure every aspect is sound. Hopefully I figure this out in the next 2 weeks!! Grrr

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How is any research on this make and model just not relevant on YouTube? Nothing as much as an oil pump service but one of a Yamaha... don't other people than myself rip these engines open and make repairs? If you know what your doing make a video? Has any one with an RMZ had some problems? Post it up schooling the game. I had enough of searching with only crf and Yamaha tutorials or only automotive results to the search. You know more people may buy suzukis if there was instructional repair videos?? Yet none... while Honda claims reliable and Yamaha has every style machine under the sun I can't help but ask why I'd hold onto this bike any longer?? An mx bike but nobody wants to fix their bike themselves? I thought I bought Japanese not German. Honestly if I have to gut this bike to make a million views on YouTube and teach a kid how to diagnose , and service his bike I'm not gonna be upset I'm just gonna learn to be a mechanic on the newest technology of the most historic bike in mx history. How the &%$#@! doesn't anybody understand the importance of the breakdown of the newest model bikes? When I call a dealership they usually hit me with some are you stupid talk it seems like we're all just trying to figure out how this Joe works when apparently someone does?? My bike is a 2012 and anything up is efi and not much different if you catch this post a year or 2 after it's post hit me up I'll help fix your issue in and out with the proper run down of what to look for where to look how to take it apart and put it back together. 100

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