1/2 crank rotation then locks up?

mr2peak · April 11th, 2014, 03:35 PM

Ok. So.

The engine will only turn over a 1/2 turn, then feels like it's locked solid. I'm turning the crank by hand, clutch is uninstalled at the moment.

I was riding it, then all of a sudden it locked on me. However it can't be frozen, because I get a 1/2 turn of the crank. What is going on here?

I also already removed the spark plugs so it's certainly not hydrolocked.

Any ideas? I'm stumped.

alex.s · April 11th, 2014, 03:41 PM

are the valves moving?

whats the status of the timing chain?

Racer x · April 11th, 2014, 03:41 PM

Timing Chain break???

Alex · April 11th, 2014, 03:47 PM

Youch! I've got nothing, other than the hope that you can track it down...

mr2peak · April 11th, 2014, 04:03 PM

Timing chain is fine.

Took off the valve cover, and the crank stops rotation when the right hand cam/valve is is at full relief. So it stops on both intake and exhaust...

Which is very very strange. The motor did sound like it was knocking, I'm wondering if the piston disconnected its self and wound up stuck up high in the bore....

This sucks. Looks like I'll need a new motor. Anyone have a lead on one in the Bay Area?

Just put up an add on BARF

alex.s · April 11th, 2014, 04:07 PM

poke a stick down the spark plug hole and you can feel where the piston is as you move it. a dropped valve would also do something similar

mr2peak · April 11th, 2014, 04:12 PM

Resorted to the "chopstick method" patent pending.

Anyway, chop stick down the spark plug hole. Both pistons move, I'm back at square 1 1/2

Edit: haha that's perfect. So must be a dropped valve then?

mr2peak · April 11th, 2014, 04:15 PM

So it must be a dropped valve? Anyone have a tech article on fixing that?

Or is this replacement motor time? This one has 20k on it

Skullz · April 11th, 2014, 05:04 PM

nvm, guess i need to finish reading the whole post before posting. lol

Open the other side and see if something hasn't happened to the stator or rotor to cause a bind.

mr2peak · April 11th, 2014, 05:07 PM

Quote:

Originally Posted by mr2peak

Ok. So.

I also already removed the spark plugs so it's certainly not hydrolocked.

Any ideas? I'm stumped.

rubber side down · April 11th, 2014, 06:32 PM

not sure how tight the tolerances are piston to head, but sounds like you might have spun the bearings around to the bottom side of the rod and piston is hitting the head??? maybe

mr2peak · April 22nd, 2014, 10:27 AM

Picked up a new motor this weekend, spent sunday getting it in, and did 150+ miles yesterday.

Gonna pull apart the old motor when I have some time and see what's wrong with it

Alex · April 22nd, 2014, 10:28 AM

Glad you're up and running.

Motofool · April 22nd, 2014, 02:00 PM

Quote:

Originally Posted by mr2peak

Picked up a new motor this weekend, spent sunday getting it in, and did 150+ miles yesterday.

Gonna pull apart the old motor when I have some time and see what's wrong with it

Check if the rotation is stopped in a symmetrical way in both directions.

If not, open the left side only first; it could be a problem with the starter's gears.

mr2peak · April 26th, 2014, 08:12 PM

Quote:

Originally Posted by Alex

Glad you're up and running.

Me too, so much fun! Over 500 miles on the new motor already. Thanks again for all the help!

Gavin_Coffey · March 16th, 2015, 09:04 AM

Quote:

Originally Posted by mr2peak

Me too, so much fun! Over 500 miles on the new motor already. Thanks again for all the help!

I had to recently do a engine swap... My dad rolled a bearing on my bike when it was brand new... Sad day...

April 11th, 2014, 03:35 PM	#1
mr2peak ninjette.org member Name: james Location: SF Join Date: Mar 2014 Motorcycle(s): Hyper 821 Posts: 161	1/2 crank rotation then locks up? Ok. So. The engine will only turn over a 1/2 turn, then feels like it's locked solid. I'm turning the crank by hand, clutch is uninstalled at the moment. I was riding it, then all of a sudden it locked on me. However it can't be frozen, because I get a 1/2 turn of the crank. What is going on here? I also already removed the spark plugs so it's certainly not hydrolocked. Any ideas? I'm stumped.

April 11th, 2014, 03:41 PM	#2
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	are the valves moving? whats the status of the timing chain? __________________________________________________

April 11th, 2014, 03:41 PM	#3
Racer x ninjette.org certified postwhore Name: Eric Location: Iowa City Join Date: May 2009 Motorcycle(s): 2008 Kawmeracchi 350 2010 Project X Posts: A lot. Blog Entries: 54 MOTM - Sep '18, Feb '16	Timing Chain break??? __________________________________________________ Top speed 123.369mph. Ohio mile Worlds fastest 250 ninja

April 11th, 2014, 03:47 PM	#4
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Youch! I've got nothing, other than the hope that you can track it down... __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

April 11th, 2014, 04:07 PM	#6
alex.s wat Name: wat Location: tustin/long beach Join Date: Sep 2009 Motorcycle(s): wat Posts: Too much. Blog Entries: 5 MOTM - Oct '12, Feb '14	poke a stick down the spark plug hole and you can feel where the piston is as you move it. a dropped valve would also do something similar __________________________________________________

April 11th, 2014, 04:03 PM	#5
mr2peak ninjette.org member Name: james Location: SF Join Date: Mar 2014 Motorcycle(s): Hyper 821 Posts: 161	Timing chain is fine. Took off the valve cover, and the crank stops rotation when the right hand cam/valve is is at full relief. So it stops on both intake and exhaust... Which is very very strange. The motor did sound like it was knocking, I'm wondering if the piston disconnected its self and wound up stuck up high in the bore.... This sucks. Looks like I'll need a new motor. Anyone have a lead on one in the Bay Area? Just put up an add on BARF

April 11th, 2014, 04:12 PM	#7
mr2peak ninjette.org member Name: james Location: SF Join Date: Mar 2014 Motorcycle(s): Hyper 821 Posts: 161	Resorted to the "chopstick method" patent pending. Anyway, chop stick down the spark plug hole. Both pistons move, I'm back at square 1 1/2 Edit: haha that's perfect. So must be a dropped valve then?

April 11th, 2014, 04:15 PM	#8
mr2peak ninjette.org member Name: james Location: SF Join Date: Mar 2014 Motorcycle(s): Hyper 821 Posts: 161	So it must be a dropped valve? Anyone have a tech article on fixing that? Or is this replacement motor time? This one has 20k on it

April 11th, 2014, 05:04 PM	#9
Skullz ninjette.org guru Name: Ray Location: 48162 Join Date: Aug 2013 Motorcycle(s): 2012 Ninja 250 Posts: 450	nvm, guess i need to finish reading the whole post before posting. lol Open the other side and see if something hasn't happened to the stator or rotor to cause a bind.

April 11th, 2014, 06:32 PM	#11
rubber side down ninjette.org member Name: Travis Location: so dak Join Date: Nov 2013 Motorcycle(s): 01 gixxer 1k, 02 gixxer 600, 02 ninja 250, a slew of dirt bikes Posts: 52	not sure how tight the tolerances are piston to head, but sounds like you might have spun the bearings around to the bottom side of the rod and piston is hitting the head??? maybe

April 22nd, 2014, 10:27 AM	#12
mr2peak ninjette.org member Name: james Location: SF Join Date: Mar 2014 Motorcycle(s): Hyper 821 Posts: 161	Picked up a new motor this weekend, spent sunday getting it in, and did 150+ miles yesterday. Gonna pull apart the old motor when I have some time and see what's wrong with it
	1 out of 1 members found this post helpful.

April 22nd, 2014, 10:28 AM	#13
Alex ninjette.org dude Name: 1 guess :-) Location: SF Bay Area Join Date: Jun 2008 Motorcycle(s): '13 Ninja 300 (white, the fastest color!), '13 R1200RT, '14 CRF250L, '12 TT-R125LE Posts: Too much. Blog Entries: 7	Glad you're up and running. __________________________________________________ Montgomery Street Motorcycle Club / cal24.com / crf250l.org / ninjette.org ninjette.org Terms of Service Shopping for motorcycle parts or equipment? Come here first. The friendliest Ninja 250R/300/400 forum on the internet! (especially Unregistered)

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
Hayabusa locks front	Floki	Videos	12	June 14th, 2014 03:17 AM
Handlebar locks	A7xschecter6661	1986 - 2007 Ninja 250R Tech Talk	2	August 22nd, 2011 05:48 PM
I so want one of these disk locks, just don't tell me the price	ninjabadger	2008 - 2012 Ninja 250R Farkles	13	December 25th, 2009 09:33 AM