A quick check.  I may have mixed the TY and RT engines up but...

Recalling my dark and very distant past maintaining TY175s.  You will remove the kick idler circlip and washer.  Remove the idler gear.  Behind that will be another washer and circlip, then a bearing retainer plate stopping the needle roller bearing from migrating out.
I doubt you would get the bearing out from there with the shaft still in though.

RT100s no.  It does not have a retainer plate, the case is a close fit around the shaft and the bearing can only be pulled from the inside.

#21 here:  www.partzilla.com/catalog/yamaha/motorcy.../dt175b/transmission

Thats the chappy.  Where the number 11 is pointing is the part of the plate that covers the shaft bearing.

 

Fits in hole looking across
www.partzilla.com/catalog/yamaha/motorcy...c/crankcase-cylinder
I'd be worried about what shrapnel has gone into the transmission that you can't see--even if you were lucky enough to hook out the remaining shell of the bearing by removing retaining cover 11. 11 doesn't look like it cover much of the circle of the bearing to stop it moving sideways. But i guess bearing should be tight in the case, so retainer just give a hint to it not to think about moving.Wonder there's not a circlip in there for the bearing to come up against.

have spoken with local mech i know who can strip it down for me and split the crank casing for a couple of hundred
not something i have the workshop space or possibly the patience to do
to try to get ahead with parts am i looking for?
yambits.co.uk/dt175-usa-twinshock-sprock...-small-p-159789.html
or am i looking for?
yambits.co.uk/dt175-usa-twinshock-main-s...-small-p-159788.html

will know more when i get the clutch basket off i guess just wanted to check if i can even get the part


as it happened during trying to kick it rather than when it was running am hoping damage will be minimal though
i
thanks all
D

You can get the bearing from Yamaha.  Don't make the mistake of buying "NOS" parts on ebay that you can buy new from Yamaha cheaper. 

I would guess that the kickstart gear has jammed, and destroyed the bearing? Is the crankcase half ok?

Its a complete strip down, and possibly a weld repair if the cases are damaged.

Any sort of kickstart problems on these bikes, should be sorted before attempts to get them running.

thanks
havent had much chance to split the cases yet, engine is out and will get the clutch basket and idler gear off tomorrow if i can
i think your assessment is correct, i think the needle bearing has blown on the kick idle shaft if thats what ts called?
have the kick gear, idle cog and needle bearing coming
hopefully no damage to casing, the damage didnt happen while it was running but when being kicked so hopefully that might minimalise damage
looking "optimistically" ahead to rebuild..
most all the kick assy images and videos have the kick spring attaching to a hole in the casing, my '76 US 175C doesnt have this but does have a pillar/shaft under the clutch which looks right for the spring to attach to considering tension and spring orientation on end?
pls see attached?
imgur.com/a/kB11ydu

cheers again



 

Have a close look at the shaft where the idler gear sits as they break of in similar situations that yours has with the bearing. Revolve it & look closely for bend--wobble.
Could just turn the rear wheel if chain is on & watch the idler gear & shaft although with bearing broken it won't be well supported for a true spin but should still give a good indication.

i can move the idle gear slightly by hand suggesting the bearing has blown i suspect?
should have the clutch off tomorrow and should know if its a crank apart bottom end rebuild which i fully suspect it will be, so will have to make a crank case splitter up and dig in
might be a good time to just get stuck in and do all bearings and seals get the cases vapour blasted while off, rewire stator,heat shrink & heat sheild new condenser
almost looking foorward to it now as a winter project