Danjet600 wrote: now i'm in 2 minds about the engine build, do i go the whole hog and split the cases new big end ect or do i just do a top end build???

I would check the gears, you can see fifth gear if you move the crank & balancer out of the way.... if the gear is ok, the rest probably will be... but as Just Dan says, you can't clean the oil strainer without splitting the cases....& as you've got this far....

The balance shaft drive gear "knock" is common on the SZR & MZ 660s, I got it on my XTZ.

It's caused by the 3mm thick washer next to ya main bearing grinding into the slotted washer next to it, which reduces the pressure holding it all together & allows the balance shaft drive gear to rattle.

The bits to check for wear (& change) are:

The 3mm thick washer next to the R/H main bearing.
Both slotted plates either side of the balance shaft drive gear (your outer 1's worn, the inner 1 will be worse).
The key in the balance shaft (there can be a knock on effect!)

Me & a mate (he's a blacksmith) decided yamaha have updated there production techniques, so new genuine washers & plates are the way to go.
The original inner washer on mine was bent & had rounded edges caused by the stamping process that formed it (this produces "high spots" that grind into the plate).
New 1's are perfectly flat with sharp edges (I ground my original flat on plate glass but have been told new 1's are ok)
The original slotted plates are plain in colour with rounded edges.
New 1's have a mottled colour & sharp edges indicating they've been "finished" & heat treated.

Rick

xtzrick wrote:The balance shaft drive gear "knock" is common on the SZR & MZ 660s, I got it on my XTZ.

It's caused by the 3mm thick washer next to ya main bearing grinding into the slotted washer next to it, which reduces the pressure holding it all together & allows the balance shaft drive gear to rattle.

The bits to check for wear (& change) are:

The 3mm thick washer next to the R/H main bearing.
Both slotted plates either side of the balance shaft drive gear (your outer 1's worn, the inner 1 will be worse).
The key in the balance shaft (there can be a knock on effect!)

Me & a mate (he's a blacksmith) decided yamaha have updated there production techniques, so new genuine washers & plates are the way to go.
The original inner washer on mine was bent & had rounded edges caused by the stamping process that formed it (this produces "high spots" that grind into the plate).
New 1's are perfectly flat with sharp edges (I ground my original flat on plate glass but have been told new 1's are ok)
The original slotted plates are plain in colour with rounded edges.
New 1's have a mottled colour & sharp edges indicating they've been "finished" & heat treated.

Rick

thanks for the info i have decided to split the motor and do the big end, as geoff said i got this far !!
any way some progress shots


got the stator side cover off



cheap shit puller started bending will have to get a decent 1 for the job

any advice on getting the flywheel off!!!
i've got the puller on and its tight i've been using some wd40 soaking it and tried to heat it no go, i've hit the end of the puller bolt to jolt it no go

Danjet600 wrote:any advice on getting the flywheel off!!!
i've got the puller on and its tight i've been using some wd40 soaking it and tried to heat it no go, i've hit the end of the puller bolt to jolt it no go

While everything is tight, try a little heat on the centre of the stator, but not too much as you can melt the outside plastic parts.

Yeah, hit the flywheel very hard with a mallet... it'll come off..... I've got one o them plastic mallets full of lead shot, it works a treat... if you've only got a hammer, put a bit of wood on the flywheel & hit that....

Yes, built up tension with the puller and give it a good smack with the hammer.
I did this to my flywheel aswell.
Not nice but sometimes violence is goooood...
Fred

Fred333 wrote:Yes, built up tension with the puller and give it a good smack with the hammer.
I did this to my flywheel aswell.
Not nice but sometimes violence is goooood...
Fred

yes well it gave me the shits so if the advice is to take to it with the hammer i'll gladly have a go

i have a dead blow hammer similar to this



where abouts on the flywheel did you give it a hit?

Just belt the ferker.

If that don't work (on the outside) it should do, get a drift or big chisel & aim it at the centre (inside) and belt it with a steel hammer.

Mezo.

Hitting on it side should do to trick if the fly wheel is under tension. It will hang in there and then suddenly let go with a crack.