yx 150 ugrade to yx 160 possible?

[user 20441]

hi guys,
i just got hold of a fairly new engine that somehow broke a valve and so breaking the piston and con rod.
i might be able to save the head but need a new cilinder and crank.
the difference between the 150 and 160 is the stroke,correct?
could i fit the longer stroke crank in the 150 cases without boring them?
i don't want to go crazy on the budget with this thing but if it would be possible, while i have to replace all the critical parts that make the difference, i might aswell go bigger then...

shoot :-D

 

[mikkh]

Yes the yx150 and yx160 cranks are interchangeable ie the only difference between yx150/160 is the crank (so no need to bore the cases), everything else is the same... Z155/Z160HO YX150/160 cylinders are intercheangeable too and heads fit, but there are exhaust port mount differences and you need a different intake manifold if you swap the head types from crf (yx heads) to klx (zongshen or kawasaki klx110) heads.

 

[user 20441]

everything interchangeable from 1st to 3rd gen yx engines?
and how about the cilinders, i know bore is 60mm but for the longer stroke you need a higher cilinder for the 160,right?

 

[user 20441]

most importantly,will i be able to build me an engine that's somewhat better that a std yx160 at the cost of 430€

 

[mikkh]

All yx150/160 and z1ˇ55 z160ho cylinders interchange.
And there are cranks with oil slinger and without oil slinger for both yx150 and yx160. Z160HO crank does not fit yx160 without z160ho clutch cover...

 

[user 20441]

imho if you put a stroker (=langer stroke from the yx160 vs yx150) ,you"ll need either a 2mm longer cilinder or a spacer and not just the exact cilinder as the yx150.
stroke from the 150 to the 160 is 4mm difference, meaning piston goes 2mm deeper in cilinder but allso 2mm higher in cilinder ,thus piston would hit cilinderhead if the deck height would not be adjusted...

but the question remains, can i build myself a better engine by repairing the broken engine with better parts that what it used to be FOR THE PRICE OF 400€.
a new yx160 costs 450€ ...
i might be able to reuse the cilinder,but full cranck,piston and possibly complete head might have to be replaced.

thanks for any advice,
Hannes.

 

[mikkh]

1. The extra stroke is compensated by shorter con rod and because of that cylinders are the same height. Well I have seen an yx160 with 5-6 base gaskets as a spacer since somebidy forgot to use cylinder head dowels and the valves were hitting the piston, too simple fix, but those hack jobs never get the idea .

I have z160ho, yx150, yx160 cylinders in my garage I will take pictures tommorow with the cylinders on floor and carpenters level on them to prove the cylinder height .

 

[mikkh]

1. The extra stroke is compensated by shorter con rod and because of that cylinders are the same height. Well I have seen an yx160 with 5-6 base gaskets as a spacer since somebidy forgot to use cylinder head dowels and the valves were hitting the piston, too simple fix, but those hack jobs never get the idea .

I have z160ho, yx150, yx160 cylinders in my garage I will take pictures tommorow with the cylinders on floor and carpenters level on them to prove the cylinder height .

 

[user 20441]

now we're talking tech!
thanks for the insight, never thought of a shorter con-rod
but do you think i can build a better engine with that limited budget or should i be better off buying a new stock engine at 450€?