Project XL185/CG250 swap

[XLsior]

Edit 42P 135M was the winter tune.


I have installed 38P 138M jets. still 4th needle clip.

[XLsior]

Might be the nail in the coffin for the this CG250...

[XLsior]

So the OG $80aud basket case used CG seems to be on the way out...


The blown headgasket ordeal might have been to much for it and it's giving up.


Oil is sweating out of it and the clacky bottom end is knocking on heavens door.


So I have some options...I while back I picked up a few used chonda engines after my catastrophic head gasket fail...


I used some parts of a Dukar CG250 to save the OG engine...So I have the option of using the Dukar core and bottom end and swapping parts over from the OG....However the Dukar looks about as abused so its a toss up how long that will hold up...


I also have some smaller displament 200cc CB/CG chondas...unknown quality.


And finally the gem being the 169FMM CB250 that appears newish* and I got to turn over after finding all that was wrong was a stuck intake valve...The issue being the valve/cam cover fouls on my modified XL350 fuel tank...


But it might be possible to dent some clearance...


Not what I had planned for the weekend as I am now in a position where all my vehicles are pit stopped for some reason.


I will try the 169FMM first...

[XLsior]

Got the 81 frame out for a test fit before committing to installing the CB250 into the 92 frame.


Would appear to fit no issue but looking under the tank the CDI and inner tank wall are likely kissing, but its close enough that I'm ok shaving 1 side or love tapping the other to call it doable.


With that information I proceeded to rip out the tired old heart 'again' and bolt in the 169FMM


Got it in before sun down.

[XLsior]

So I got the 169FMM running...


Good news is that it runs and all gears work...


Bad news is that the clutch is stuck and there is significant blow by...


So its seen some action.



It hot starts pretty well so I'd say the compression is fair and the blowby might improve with more use as I suspect the cylinder and rings might be rough from neglect/sitting.


However Is it worth investing more time and effort into?



I am inclined to use the Dukar CG250 core and swap all the bits over from the busted bigend CG250 OG...


Sorry for thumb in vid shot...Honestly all the gears shift and there is neutral...

[XLsior]

So now I had to establish if indeed the bottom end was bad...


after removing the top end on the clacker and comparing it to the Ducar...


I came to the conclusion that they are about the same...


Nothing jumped out suggesting the crank or rod was bad...


So with that piece of insight I have elected to keep running the OG.


Seeing as I went this far I opted to install the 70mm DYNOP flat top piston and send it...


it's just gotta last 6 months of small errand work...and maybe a 700km return trip at Christmas.


Then it can keep leaking oil and collect dust under the house...


The 169FMM will likely go into the 81 frame. As i would have to modify the tank and header pipe to make it fit in the 92 road bike.