Runs like choked all the time

[Jerry Hall]

Pistons typically go by .010" bore sizes. .010" = 0.25mm. so it is a 67.75mm piston

  Measure the bore.  If the piston measures 67.75 it is probably a worn out 68.0 mm piston. The piston's largest diameter is usually the bore size minus the piston to cylinder wall clearance.  If the bore size is 67.75 the piston's largest diameter should be around 67.65 to 67.70mm

[PorP]

Pistons typically go by .010" bore sizes. .010" = 0.25mm. so it is a 67.75mm piston

  Measure the bore.  If the piston measures 67.75 it is probably a worn out 68.0 mm piston. The piston's largest diameter is usually the bore size minus the piston to cylinder wall clearance.  If the bore size is 67.75 the piston's largest diameter should be around 67.65 to 67.70mm

Thanks Jerry.  The part# verified it's 68mm. I did measure the bore.... on my calipers it was coming up 67.85-67.9.

I then measured a brand new 66mm piston at 65.75.

My calipers just seem to be .25mm off at the bigger measurements despite being zeroized.

[2ndmoto]

Glad you found it

[PorP]

Well,  I'm making 185-190psi on this new top end.  Waiting on the new cdi now.  Hopefully that fixes it.

Otherwise can I use a cr cdi with the trx flywheel and stator?

[2ndmoto]

Have to run cr stator and flywheel. Also need a stator plate

[PorP]

Hey folks,  I haven't touched my R in a year due to life changes.

But I got a leak down tested,  Found it was leaking from the rear cylinder base bolt threads on the left side.  Leaking as fast as I can put air in. I got it in the sunlight and found a crack that runs along the cylinder bolt.  I am assuming it is cracked in the inside too.

Question is,  can this be repaired with welding?  Worried about crank clearance.  You guys know as well as me left cases are hard to find so looking for other options.

I do have a pic of the crack but can't remember the hosting service I used.

[croat1]

Hey, we all know things happen but welcome back.  Take a picture with your phone and store it.  Make a reply and then hit the attachments and other options icon.  Next choose a file to attach from your photo library.

Joe

[croat1]

Billet cases have been recently released if you want to go that route. 

Joe

[PorP]

You can zoom in,  that crack runs to the top.  I do not see the crack on the inside but based on how it's leaking,  pretty sure there is a crack behind the crank.

[PorP]

You can zoom in,  that crack runs to the top.  I do not see the crack on the inside but based on how it's leaking,  pretty sure there is a crack behind the crank.

Joe,  I saw that,  but they are like 2/3 the cost of a fresh built complete motor.  Unless you are talking about a different product?