Hello! Starting the restoration of an Ascot Scrambler. Any guidance about user groups, blogs, etc. is appreciated. Seeking an owners manual specific for Ascot Scrambler (does it exist?). Seeking mechanical drawings/vendor information for fabrication of the expansion chambers and the air filter assembly. I have found and ordered some used parts via eBay. Thanks for the assistance!
Welcome to the forum The Factory Service manual is here in the resource's section, not sure if it cover's the Ascot Scrambler though ? There is a 23 page Tuning Theory section with calculating compression ratio's, expansion chamber diagram's etc etc for Street, Scrambler and Road Racing @mboddy may know if it does or not ? To download the service manual etc, you'll first need to upgrade to a Premium member https://2fiftycc.com/index.php?resources/categories/yds3.61/ There's a link highlighted in yellow near the top of the page, click on it and pay the $10AU via paypal and you'll become a Premium member Any pic's of your bike ?
YDS3 is earlier than I have had but I did have a mate at school who I recall had either a YDS2 or YDS3. I do have a few Yamaha books though. I looked up the Ascot Scrambler in Yamaha two-stroke twins by Colin MacKellar. Yamaha originally produced a scrambler kit for the YDS2 known as the Ascot Scrambler. The YDS3 had two Ascot Scrambler variants; YDS3C was a dual purpose bike and YDS3CM was the serious competition machine. The YDS3CM had the same engine as the TD1B. Yamaha YDS3C Yamaha YDS3CM
Thanks for the YDS information, my bike appears to be a YDS3CM. It is near-complete dis-assembly with focus on parts inspection, cleaning, rust removal and proper interim storage. I will provide pictures at a future date.
Working with two engines to create one rebuild. Challenged to remove clutch assembly from shaft. After the large nut and flat washer is removed, there appears to be machined semi-elliptical clips embedded at end of shaft (reference attached picture) and I have not successfully determined how to remove them, seeking guidance. I have reviewed three Yamaha YDS service manuals, however, the step-by-step how to not provided.
My 1965 YDS3CM had an aluminum barrel with an iron liner, where the TD-1B had an aluminum barrel with hard-chrome plating. I believe that the 1964 and prior Ascotts did use the TD-1 engine. At least the prior years' expansion chambers had the same look for both models. My bike's primary gear-drive was helical instead of the TD-1B's straight-cut. The TD-1B made power from 8K-10K. My Ascott made power from 6K-8K. I later, converted the Ascott's engine and expansion chambers to TD-1B spec. Using street exhausts, the rev-band was reduced to YDS-3 level; I could easily ride the bike in town. Although not my bike, here is a photo of the 1965-66 version. Note the larger air filter housing.
A "fun fact" for you all: the Ascott's and TD-1B's clutch hub, backing plate, was a weak casting. It would fly apart with normal, racing use. The "trick" set up was to machine a backing plate from aluminum, per Yamaha's drawing. I never saw a failure after installing that.
