Well here's what i did. I looked up the part number for the shaft, # 21421200. No one carries it, Tower Hobbies or anyone else, just a few ocscure entries on Google, I call OS and ask if the part number has changed. Mark Looks it up and said yes to 21812200, the same as the .18 CV-RX. I check Tower Hobbies and there it is. I check the Tech Notes and it said fits the .18 but no mention of the .15 (mine). So being the kind of untrusting person I am, I disassembly mine to measure. The length of the new shaft is 19MM, mine is 22. The other dimensions are the same. I then notice the plastic PS wheel has a groove worn into it, not deep but it's there. Imeasure the amount of the shaft that protrudes from the OWB and it's 3mm!! So I carefully insert it into my lathe and removed the 3mm. Cleaned and reassembled using Magnalube Grease (Google it, best stuff made -I sell it in my shop) and I pulled and pulled (without the GP ignitor), it will not slip. Only time will tell if it really is fixed but it works as it should. So OS must have had problems with this and determiined the shaft was causing the problem and the new ones are a different part number. Remember, when I say new, my engine was purchased new in 2000 but had not been used since 2001 so whatI considers the "new" design most likely has been out for years.

Thank you for your help and sorry for the long post - like to be thorough.