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ID this piece in crankcase! 94 xr250r

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Hey, new member here, my name is Josh.  Been looking to get on a bike as I'm growing tired of only having the blaster, so been reading on here about a good beginner bike for myself, and started looking for xr250s.

I ended up a project 1994 xr250r, with a broken kick start return spring.  (According to PO).  He said he picked it up as a project himself but time got away from him.  Many oil leaks on this thing during the time I did get it to fire... all valve adjustment caps on rocker cover, oil line fitting at oil cooler, all engine mount bolts loose, 2 hex caps on inside of cyl head by spark plug leak, missing rear brake pedal, kickstand. 

Also Found a pile of JB weld on clutch cover right above kickstart.  (Covering g auto decompression shaft orifice)..  I Pulled the cover, and find spring is not broken, but installed on opposite side of casting boss in crankcase.  Auto decompression parts Missing in crankcase it seems as well?.  Well after I pulled out kickstart shaft to reseat the spring, noticed a bolt was missing from bracket that mounts toward rear of engine and holds the tab on the kicker shaft...  Started feeling around with a magnet through the crankcase looking for the missing bolt, and pulled this part out..  what am I dealing with here?  Seems like I may need to pull motor and go through it huh...  Can anyone ID this small piece and recommend where to go from here?

 

Working with different cars over the years it almost looks like a relief valve plunger for the oil pump... Anybody confirm?

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If this was really someone's failed project bike I suppose it's possible it's not part of the engine or transmission at all..?  Part of a tool? Too short to be the tip of a chain breaker though..

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i split the crank cases on my xr250 recently and i don't recognise that. 

I'd go with it's the tip from a puller.

seems like you could use a new engine/clutch cover. I had to replace the other side a while back, found the part on ebay delivered from USA for a reasonable price after a while though there were some people asking silly prices and not selling them.

Edited by FFMan

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The little piece was hardened.  Some gouges on it like it got stuck in a gear however...At this point the piece's origins matter less and less... Here's what I've been up to.

I decided since I didn't fish out any more steel (there were aluminum chunks in there though, but were stuck under sump pickup screen) that I would just properly install the Kickstart and see how the engine sounded, and if I could get it to rev at all to check for smoke, etc, and go from there.  I adjusted the valves and cleaned the carburetor.. still no go.  Figured I missed a passage, and cleaned it again.  Basically it would only idle io full choke, wouldn't rev, would just bog out. 

After 4 cleanings and not seeing any improvement, I busted out the leak down tester.  Popped it in and pressurized to  25psi.  Rotated kick start by hand to position with valves closed - no audible air leakage from intake or exhaust, good kick back from air pressure, but slight hissing heard from crankcase with dipstick removed.  Fired up engine again, full choke, let it idle about 5 minutes, still won't rev at all, stalls at any throttle input no matter how small...

Next step was compression test, which read 79psi (warm, dry) with the hardest and fastest kicks I could muster.  Wet test bumped up to 111psi.  Figured I would take it apart and inspect, and upon removal of the rocker cover, found (besides 2 stripped rocker cover bolt holes jb welded over) evidence of camshaft or catastrophic gear failure in the past via large gouges in the head casting , as well as the camshaft tensioner set plate and 2 long bolts missing, locating dowels for camshaft end bearings MIA, center cam journal scarred, 2 cam lobes pitted, and chain tensioner wedge fully receded into the tensioner body.....  (For some reason I did not verify current cam timing at this point, don't know why - bet timing was off)

Pulled the head and yep.. piston to valve contact on intake side.  Except the valves were brand new, perfectly clean, and sealed well.  Top piston ring end gap measured .032", 2nd ring end gap .036" - well worn.  Bore mic'd out at 73.047mm, piston scuffed on thrust surfaces.

So....

Previous owner sucks at working on and maintaining stuff.  Probably had cam timing jump from something major and had valves replaced and tried to put it back together and forgot a bunch of parts (and dropped in a few extras I guess).  Since all engine mounts were loose, I assume he's had his grubby hands all through it, and I have some work ahead of me to make sure it is built correctly....

Probably was out of time.  May have smoked due to ring gap but I bet it would have ran.

So..

Long winded post,  just wanted to give a detailed description.

Most expensive cheap bike ever.  I'll see if I can update post with pics in the morning.

 

Edited by apexrift
Exact clearance info added
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Already ordered all parts I could see I needed so far...  Whoops..... Only 337 so far but still need cam and machine costs.  got screwed on bike cost / issues ratio (500).  Trans itself felt ok during the time it idled.  Shift drum felt smooth, all forks functional... Crank feels great.  Not sure what else I'll find but I will update, probably will play with it tomorrow a little

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WOW  sound like you have your hands full.  all I can say is at least if the frame, suspension, wheels and so on are good and its just the engine that's been screwed with (all though expensive ) once you go through it all you will have a known quantity. is it worth looking for a parts bike the same as the one you have? may be easier and cheaper to swap some parts instead of getting them machined. and if you intend on keeping this bike for some time spare parts add up quick its not hard to justify the cost of a parts bike over time.  

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UPDATE:  Everything has been disassembled down to transmission gears - cases split.  I ended up finding the missing bolt for the kick start retainer plate, and plenty of metal shavings (aluminum).  Cam Chain is Chewed up on approx. 9 links.  cannot flex...   ALSO

 

I FOUND WHERE THE PIECE GOES!

Is it's intended purpose to limit the travel of the decompression cam on the kickstart shaft?

 

xr250r <a href='https://thumpertalk.com/link/click/1135/' rel='nofollow' data-ipsHover-target='https://thumpertalk.com/index.php?app=autolink&module=links&controller=content&id=1135' data-ipsHover target='_blank' rel='noopener' data-autoLink>Clutch Cover</a> Bad Paint.jpg

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Well replacement case has been ordered.  Gearset looks good, crank and bearings all ok.  Just got cylinder and head back from machine shop, went big bore.  Still waiting on a few parts from partzilla and it looks like I'll be in business. Total cost for replacement parts and machine work $525... $1025 total bike.  Lots of time though.

  If that piece is designed to limit travel, any ideas on what caused it to break in the first place..?

Looks like it broke out, got jammed up in cam chain and boom. Likely PO replaced valves and then gave up when it wouldn't start.  Center cases weren't touched thankfully and all parts are there inside haha

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