Hello. I'm brand new to the forum, as I have just begun working on an early Yamaha twin that I acquired in 2004. I'm hoping someone will be kind enough to help me identify the model, because I can't find much info about it. The title says it is a 1966, but doesn't provide the displacement. The headlight nacelle says YHA-1. If needed I can provide pics or the serial number. It has all the original paint (red and cream color), and is a streetbike with low exhaust pipes and fenders. If anyone can give me a clue it would sure make it alot easier to order parts. Thanks.

Welcome...Yes a pic and serial number would help

...Paul

an early Yamaha twin The headlight nacelle says YHA-1. If needed I can provide pics or the serial number. It has all the original paint (red and cream color), and is a streetbike with low exhaust pipes and fenders.

Welcome heatRfan Is it a two-stroke ?? lookn up some in mags now ?? YDS 5 YDS 3 here

Welcome heatRfan Is it a two-stroke ?? lookn up some in mags now ?? YDS 5 YDS 3 here

Yes, it's a two cycle twin. Did Yamaha even make 4 cycle bikes in 1966? Anyway, I think YHA-1 is actually the model number from what I can gather. I'll provide the serial number later today. I have seen some pics of the "big Bear" (not the quad or the early scrambler) and I think that is what it is. Now I just need to find some of the rubber intake hoses and I think it will be complete (I hope). Any good sources for these old parts or repro. parts? Thanks for the interest and I'll keep you posted on my progress, with pics.

Welcome...Yes a pic and serial number would help

...Paul

OK, I can provide the number later today. I partially disassembled it today to free up the carb slides, so I'll wait to post the pics untill it's reassembled. Thanks. Mike. Serial number is Y23235**

OK, I can provide the number later today. I partially disassembled it today to free up the carb slides, so I'll wait to post the pics untill it's reassembled. Thanks. Mike. Serial number is Y23235**

From that serial, it looks like you have a YDS3 as previously mentioned. It was also called a Catalina in some areas.

http://cyclerestorer.com/pages/show_man_serial_num.php?sort_field=4&manufacturer=Yamaha

From that serial, it looks like you have a YDS3 as previously mentioned. It was also called a Catalina in some areas.

http://cyclerestorer.com/pages/show_man_serial_num.php?sort_field=4&manufacturer=Yamaha

Great! Thanks for the responses and help. Mike.

FRAME# Y33-38508   MOTOR# L1-38508 YAMAHA TWIN JET 100 

Nice, but after 8 years I think the op may have it figured out.