Mikeys 73

[Mikey]

I thought they had a Yamaha logo on top

 

[jetmechmarty]

I thought they had a Yamaha logo on top

Mine does not.

 

[Niels B]

I have several xs’s 75-78 none have logos on the top

 

[Mikey]

If I go to partzilla or whoever the 73 has a different setup. I just re did like the 75 after opening the 75s cap open to make sure I did it right

 

[gggGary]

70-72 have the logo

a list of bikes that use a cap like yours
Well this list has some obvious errors or it's a conflation of two different cap types.
I marked some obvious wrong answers.

Yamaha Motorcycle 1973 TX750 Fuel Tank

Yamaha Motorcycle 1973 TX650 Fuel Tank

Yamaha Motorcycle 1974 RD250A Fuel Tank

Yamaha Motorcycle 1974 RD350A Fuel Tank

Yamaha Motorcycle 1972 XS2 Fuel Tank

Yamaha Motorcycle 1973 RD250 Fuel Tank

Yamaha Motorcycle 1973 RD350 Fuel Tank

Yamaha Motorcycle 1974 TX750A Fuel Tank

Yamaha Motorcycle 1970 XS1 Fuel Tank

Yamaha Motorcycle 1975 RD350B Fuel Tank

Yamaha Motorcycle 1975 RD250B Fuel Tank

Yamaha Motorcycle 1971 XS1B Fuel Tank

Yamaha Motorcycle 1973 TX500 Fuel Tank (1)

Yamaha Motorcycle 1975 XS500B Fuel Tank (1)

Yamaha Motorcycle 1974 TX500A Fuel Tank (1)

Yamaha Motorcycle 1975 XS500B FUEL TANK 2 XS500B

Yamaha Motorcycle 1975 XS650B FUEL TANK TX650A - XS650B

Yamaha Motorcycle 1974 TX650A FUEL TANK TX650A - XS650B

 

[Mikey]

Mailman any opinion on this
I'm not saying you guys are wrong just the parts sellers show it different

 

[gggGary]

Be real careful with 73 parts fiches many of them mistakenly use 72 diagrams/parts instead of the correct 73 pieces..

 

[gggGary]

Mikey I've had 4 or 5 73 tanks through here.. They all use the cap you have.

 

[Mikey]

Yeah it seemed strange that a newer cap would just fit right on
New caps rebuilt like a 75 and no leaks

 

[gggGary]

The fiche shows both types of caps.

 

[Mikey]

Saw that just rebuilt like the 75
While waiting for parts I decided to polish the left cover
Blue dico dics then rouge then brown compound
Still didn't look good
Good old blue magic

 

[Mikey]

caps for both the 73 and 75 are done
I noticed one thing as I was putting them back together #6 of the parts diagram has on one side 3 nibs / nubs /bumps that I just thought were a result of poor molding process but those 3 fit into holes on the part in the photo I'll attachI would assume thats to align the breather hole properly during assembly

 

[Mikey]

I know parts replacer question
I'm in garage so I can't post videos of the bike running ( it now does poorly)
Any the question is the points look way off at least one set
Both sets don't open at the same time ?
I know dumb question
The top looks to be at 12 thousands
Bottom one a lot less.
And do I need the missing sticker showing TDC it's missing

 

[Mikey]

Here's what it sounds like running now

And a picture of the top and bottom points
And a picture of the area where the timing sticker used to be

 

[Mikey]

A friend that is mechanically inclined than me (which doesn't take much) Thanks Ralph
So the points don't open at the same time
I thought I read somewhere here about a wasted spark ignition making me think that both set of points would open at the same time
NOT
Anyway this is what he sent me and now it's starting to make sense

 

[Mikey]

I gotta get a laptop out there the wifi is sketchy at best

 

[Jim]

Yes, that's a good video to go by.

 

[Mikey]

So did I actually read something o here about wasted spark ignition for 650's

 

[Mikey]

So did I actually read something o here about wasted spark ignition for 650's

That had me going around in circles

 

[Jim]

'80 and up TCI and about all aftermarket electronic iggys are wasted spark.