Thursday, June 21, 2007

R5 Wiring Diagrams

Ok kids... a lot of you have been asking about electrical issues. Seems these bikes (as just about anything 30+ years old!) have a bunch of gremlins, and it can be a real pain sorting everything out. I'm in the middle of it myself. So I thought I'd revamp the diagrams on the site as well as highlight them all in one post here.

- R5C Wiring Diagram - from the 1972 Rider's Manual
- R5F Wiring Diagram - not a US model
- RD 250/350 Wiring Diagram - for reference, should you need it

Also here are two diagrams tracing the physical wiring harness as shown in the factory Service Manual to help you locate everything:

- R5C Wiring Harness Diagram 1
- R5C Wiring Harness Diagram 2

And finally, here is a link to a PDF of the electrical section of the factory Service Manual (via OMP).

Gotta love all the hand-drawn complexities and typos throughout! Anyways, I hope this helps!

The German Roots of Yamaha Motorcycles

Good article over on the Kneeslider about the German roots of early Yamaha motorcycles.

Wednesday, June 20, 2007

Great Reader Mail

Dave Hess from Selinsgrove, PA, wrote this excellent letter to me earlier this week. Stuff like this makes working on this site worth the while:


Two months ago my mother had to move to an assisted living home, so we had to clean out the old homestead. I came across my old Yamaha R5B I parked in her summer kitchen (shed) back in 1979. Wow, what a mess! I was going to roll it into the dumpster we rented but my brother told me I should try to get a few bucks for it on ebay. When I checked the prices these old bikes were bringing on ebay I just about fell off my chair! I decided to try to clean the bike up in hopes of upping the value of the old girl.

Needless to say, when I saw the shine come back on those fenders and the mandarin orange paint come back to life, it took me back to my college days when I used to jam a few bucks in my pocket and disappear on my R5 for days on end. That old sense of freedom I had back when times were much simpler struck me! All I wanted to do was fire up my old R5, listen to her throaty two-stroke rumble, smell the blue smoke coming out of her exhaust and ride into the sunset! I remembered riding with a gang of my friends back in the 70's, and just what a performer my bike was. They all had bigger bikes with far more cc's, but my R5 just blew them all away.

In doing research on the bikes I came across your website, which I must tell you is a real breath of fresh air. It shows the genuine appreciation you have for the Yamaha R5's and it has really motivated me to get my bike back on the road. Needles to say, I'm about half way through my restoration project. I'd like to share some pictures when I get a chance.

Thanks for the site. It's a real pleasure and something I look forward to seeing when each update comes to the net!

Dave Hess
Selinsgrove, PA

Dave, thanks for the great letter! I'm also very proud to know I played a (small) role in getting your bike back up and running. Please send in those pics and keep us updated!

Saturday, June 16, 2007

Rebuilding the Carbs

Finally got a nice Saturday with no real plans - except tackle the R5's nagging problems, of course!

Drained the oil and transmission fluid, cleaned the carbs, and right now the bike is slowly coming back up to charge. We'll see how I did soon enough...

Friday, June 8, 2007

Jesse Writes In

Jesse from Arlington, Virginia, writes in to share some pics of his newly-acquired R5 and ask a few questions:

Hi Lawrence,

I just came across your R5 website. Very nice! I just took posession of my 1st R5 this weekend. It's an orange 1972 R5C that is need of some restoration. I have restored 4-stroke British bikes in the past (I'm currently riding a 1978 Triumph) but this is my 1st 2-stroke machine. Are there any listservs, discussion boards, etc. that focus on the R5 or Japanese 2-strokes in general?

Good-lookin' bike, Jesse! Love the exhaust! You can see more of Jesse's bike on his Flickr page.

Jesse raises a good question in his email. I've gotten a bunch of similar emails from other readers who are looking to ask questions in a firum setting. I've come across a number of sources for R5-related info in my research - here are a couple of links:

Here are some discussion groups:

Yahoo! R5 group -
Yahoo! YDS Owners group -

A couple of other forums to try - much more generic, for a wider variety of bikes:

USA 2Strokers -
Cycle Forums -

There are also some shops out there dedicated to these bikes. Some good ones that come to mind are:

Moto Carrera -
Spec2 -
Omar's -

Check out the links in the sidebar for more. Hope that helps!