HELP..cg125 weird fault.....?

[davatheo]

Have bought an 07 cg125es4 (Brazil) as non runner. Good condition showing 11000 miles.
Engine has been apart at some time. Guy i got off said all he did was change gear selector shaft.
Engine will only turn over when bike pushed BACKWARDS in gear???
Piston and valves all moving freely looking down plug hole and clutch works.
Any attempt to push bike forward in gear seems mechanically locked and clutch basket moves slightly as if fault/Jam is behind it...?

Have checked everything I can think of,starter gear all free,had right engine casing off and checked clutch plates and gear selection...All operate fine.
So my question is What could possibly be going on ? and I hope I am wrong in thinking I may have to strip whole engine !

[-]

With the side casing off, it should be easy to take stuff off such as the clutch to see where it’s jamming up, as this will disconnect engine from gearbox.

If it’s gearbox, then have a look at what the twats done with the selector shaft install.
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TZR250 2MA road, TZR250 1KT road, TZR250 2MA race, TDR250, YZF-750R Boost colours.
Jaguar S Type 3.0 V6 Sport R, VW Transporter T5 GP LWB Shuttle 140ps DSG.

[stinkwheel]

I wonder if he's got the cam timing out and you're hitting a valve.

Or the starter pawl.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Easy-X]

If you take the plug out (so there's no compression, ignition off obviously!) will it roll backwards a fair way? As in the piston can move up and down freely?
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Royal Enfield Continental GT 535, Husqvarna Vitpilen 401, Yamaha XSR700, Honda Rebel, Yamaha DT175, Suzuki SV650 (loan) Fazer 600, Keeway Superlight 125, 50cc turd scooter

[davebike]

Sounds like cam timing out I seen it before owner re build !
____________________
Dave
NC750Xdct + others at work !
davebike1@gmail.com

[davatheo]

Thanks for your replies and thoughts fellow shed dwellers.
Couldnt get clutch plates out(damn castellated nut,cent oil filter,and not manufacturing my own socket... yet)But they all seem free and clutch operates to disconnect drive when pushing backwards in gear,and yes will turn over all day backwards with no dodgy noises or resistance or any fouling of valves etc....Sooo, I favour Daves theory,Cam timing (180 ?) out.
Will post solution when done...strange fault. I hate mysteries me !

[stinkwheel]

The proper honda castle nut socket too isn't very expensive. Also impact grade so you can put it in a burp gun. Flywheel puller is also surprisingly cheap.

I was surprised when I found out and wondered why I didn't buy them years ago when I found how much easier it makes the jobs.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.