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XR250R new stock cam, now not running

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Just got done with this >http://www.thumpertalk.com/forum/showthread.php?t=1030209

I put it all back together, and now it wont start. I tried all the different starting techniques until I thought my foot was broken! This thing used to start in one kick with the hot cam.

The only difference I notice between the hot cam and the stock cam are that:

1) the new stock cam isn't melted to hell

2) the new stock cam has a one-way clutch on it.

Is the one-way clutch the problem? I'm so frustrated I'm about ready to just take a grinder to that one way clutch and show it who's boss LOL.... because I can.

Of course I set the timing right, adjusted the valve clearances, made sure my carb was ready to roll, all that. Kick, kick and kick and all I get are pops. Tried bump starting and no go, just pops and pops.

It ran freaking perfectly when it was all jacked up inside. Now it's all fresh inside and it wont even run. :bonk::banghead::smirk:

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The stock cam has the auto decomp, the hotcam doesn't - did you now fit the auto decomp spring and pin in the head?

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Pull the valve cover and check it out one more time, poping tells me your 180* off.

The RFVC engine has a wasted spark ignition, fires every crank revolution. It is not possible to get the cam 180 off. I would recheck the cam timing and valve adjustment.

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Not sure if I have the proper components for use with the auto decomp cam...

I am going to disassemble and this time take pictures of everything. I checked and re-rechecked the timing and valve clearances at least 5 times. I was positive I had it right. I'm not new to setting timing and valve clearances, but I'll try it all again.

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AFAIK a stock cam bike won't run without the spring and plunger fitted. You had a hotcam till now, that means these parts were not fitted, so if you haven't retrofitted them now, there's the problem.

See this thread how they look:

http://www.thumpertalk.com/forum/showthread.php?t=1014455&highlight=plunger

You can check it by poking in from the valve cover caps.

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AFAIK a stock cam bike won't run without the spring and plunger fitted. You had a hotcam till now, that means these parts were not fitted, so if you haven't retrofitted them now, there's the problem.

See this thread how they look:

http://www.thumpertalk.com/forum/showthread.php?t=1014455&highlight=plunger

You can check it by poking in from the valve cover caps.

Hey thanks for that thread. I wasn't the owner when the hotcam was put in, so I don't have these parts. Will this really cause the bike to not run? Seems to me like all it would do is make the auto decomp not work, which shouldn't make the bike inoperable. I just want to be absolutely sure that I really need to order these parts before I do. Has anyone disabled their auto decomp before? Can you just grind down the bumps on the one-way clutch? Haha.

Found this: http://www.thumpertalk.com/forum/showthread.php?t=957282&page=4

I need to either disable the auto decomp on the cam or get those plunger parts. Any suggestions?

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Excellent :bonk:

Looks like this thing will be running soon!

Don't leave us sleepless for so long, what was the outcome? :smirk:

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Don't leave us sleepless for so long, what was the outcome? :bonk:

The plunger and spring are still on order. I think I'll have them in hand in a few days, and after that it should only take a few hours to get it going. I'm just as anxious as everyone else :smirk:

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:bonk::smirk::lol::bonk::smirk::lol::lol::lol::lol::lol::lol::lol::lol::lol::lol::banghead:

plunger and spring came today. Took the spring out and was about to put it in when the thing fell out of my hand and into the never-ending crap pile of my garage. That thing is gone for a century. That $20 or whatever spring, gone. Luckily I found a pen that had a similar spring. I threw that spring in there. I hope it works!

*EDIT*

WOOOOO it worked haha. Thank you random chinese pen on my table this morning!

After a couple kicks and a BIG cloud of black smoke from all the gas that got trapped in the cylinder and exhaust earlier, the bike fired up. I did the break in procedure for the cam, and now I'm waiting for it to cool down to change the oil out and inspect the valve clearances. On a side note... My DDM tuning 4500k HID is pretty sweet! It's a perfect white color. No blue at all.

Edited by gabechroust

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Glad it worked out :smirk:

Why wait for the oil to cool to drain it? I always thought it should be drained when hot, it flows better and you get more out.

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Glad it worked out :smirk:

Why wait for the oil to cool to drain it? I always thought it should be drained when hot, it flows better and you get more out.

I let it cool to where it's just on the warm side. It always seems to drain right out on to my hand...

Well tonight's ride was good minus my battery draining issue with the HID. The nice new stock cam definitely has heaps more power and response everywhere compared to the worn Hot Cam. Kick starting is a breeze now with the auto decompression.

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