YAMAHA 80cc Dirt Bike Questions

[Flatlander]

Hello everyone,

I am redoing a dirt bike for my 11 year old and looking for some info on it. Carb float height and adjustments, oil capacities and specs, and just some general info on this bike.

It is a Yamaha 80cc, about a 1980 or so. I am looking for info on how to identify this bikes age. The year is not stamped on the neck. The Mikuni carb has a 1T0 60 stamped on the side of it.

I have been searching the net and I have come up with nothing on this bike and would like any info or suggestions as to were to find some of this info.

Thanks in advance,
Flatlander

[Brian_D]

not much help....

you may try starting HERE. Click the button labeled 'Proceed to Parts Catalog', then use the drop downs to select a year and choose a model #. At least with Yamaha, the engine size is usually part of the model (ie YZ80).

Also, both the frame and the engine should be stamped with a number and you can cross that to the the info found under the SERVICE DATA heading for the particular bike.

The Honda that I picked up has a factory tag with most of the service data attached to the frame......I still have to use a magnifying glass to read it though.

[Flatlander]

Thanks for the site Brian

That is a pretty good site to look for things, thanks!

Just don't know the year.....clicked around on a couple of years and parts to find something close, but spent about a day or two doing that and have not come up with the right year and model.?.?

I am able to get the serial # off of the neck and it matches the motor.

Just am not able to find out info on parts or specs on this thing.

I think that a new piston and ring job will do this thing wonders. And some brakes......I about ran over the lawn chairs, taking it for a quick spin.

I did get it running and it runs pretty good, it does load up at high rpms. I have been able to adjust lower rpm with the low speed adjustments. Float height adjustment might be way off too.?.?

Just thought I would give a update on this.

[Brian_D]

hey, post the frame/engine #. I may be able to dig up something.

We (my son and I) got his XL100S tore down....2 bent valves, stretched cam chain (could manually move it forward and back a tooth), worn cam shaft, and worn cam holder. Trying to win an 02 head and cylinder on ebay....we may be able to get it running again

[Brian_D]

shazam

according to the website HERE or HERE, you have a 1977 Yamaha YZ80....of course when double checking this thru Yamaha's web site, I noticed that the first page of SERVICE DATA listed under the 1977 YZ80 is actually for the 1979 model, the second page of SERVICE DATA is for the 1977 model year.

[Flatlander]

Thanks Brian(The Wizard)D,

That is what it is, a 1977 YZ80D. Now to start ordering parts! And start looking for technical info.

Thanks,
Flatlander

[Brian_D]

ahh, me thinks you are too generous with the compliments...

don't forget, it was dad (you) that knew where to go to ask the questions and find the answers. something, no doubt, your son picked up on and will remember for the rest of his life.

[Crazcnuk]

Just rebuilt a '92 CR80 (siezed rod bearing) and the carb on a '87 PW80.

They are pretty simple. Not many parts in the carbs.

Racing bikes, like the CR, are made so that you set the carb each time you go out. It has settings that change depending on the temperature and altitude your at that day.