KR-1S.co.uk Forum

500bernie wrote:Hi Jan,
Frank from Nikon said they used to use the DT125 pistons.
Cheers
Bernie

I'm not looking for other piston's, I'm quite happy with my YZ's

it was to send to are new french member

I'm happy with my wisecos

500bernie wrote:I'm happy with my wisecos

me to

My only concern is the cost .......at 150 each they are expensive

My Mitaka (older Jap made not Taiwan) have 1KT embossed inside them,DT 125R and TZR fitment.
anybody used Vertex?

dave32 wrote:My Mitaka (older Jap made not Taiwan) have 1KT embossed inside them,DT 125R and TZR fitment.
anybody used Vertex?

I'm not 100%, but it's possible the engine I built for Bob had Vertex pistons fitted. The head and squish was already set at 0.8, so I didn't really touch the top end, just checked it over really.
From my observations though, they were a good quality piston and the engine was running well after its run in period.

Yes I am using DT125 vertex pistons in my KR:

viewtopic.php?t=8261

Prospective users be warned. The compression height is 29.90mm compared to the KR's 29.50mm. However this is to the timing edge of the piston, there is a chamfer on the edge of the piston so the true compression height is higher than that.

With stock base gaskets, stock height barrels and a totally stock head this put my squish about 0.65mm.

I have put the bike together with 0.8mm base gaskets giving a 1mm squish on my bike.

So BEWARE the squish/head volume will need to be checked to be safe.

Lovely made piston though, I modified mine slightly to line up with the cut-outs in the base of the barrel slightly and drilled the exhaust bridge lube holes. Bike has lots of compression and runs fine, just haven't ridden it yet.

Dan

Also!!!

They need a 17.50mm wide small end bearing instead of the 19.5mm stock item.

Dan

JanBros wrote:did anyone on herer save the file in my first post about the KDX125 poston ?

I haven't got it anymore

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