Other Questions about mYamaha yz80

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RichyRich23

This is my first time posting, if I do something wrong please let me know. I'll try and provide as much information as i can.
I have a Yamaha yz80 I'm not sure what year it is. First question is there anyone who can help me figure out what year it is??(I'm guessing it's around the 1980s)
Is there any I can install a stiffer shock/fork setup??
I'm having problems with the powerband. It seems to run fine at lower Rpms, just before it hits the powerband it bogs down in the top gear, the rest of the gears it acts like it's hitting a rev limiter. The bike won't start cold unless i push start/bump start it. Once the bikes warmed up it'll start with one kick.image.jpeg
 
2strokesteve89

2strokesteve89

Welcome to DBA Richard, first off you've got a 1982 YZ there. Not sure about the question concerning the stiffer suspension, I maybe check out some of the vintage swap meets on Facebook possibly.as far as your midrange bog and hard starting, I'd start by checking compression, if it's low I'd start there, if it checks ok (150 ish) then I'd move on to pulling the carb, cleaning it thoroughly set the float properly. That should be enough to get you started, oh yeah, try to locate a manual if you can, they have lots of good information in there as well. Let me know what you come up with.
 
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RichyRich23

How was you able to tell what year it was? Okay I'll check the compression tomorrow, Im cleaning the carb tomorrow. Im pretty sure I get one off eBay. Thanks for the help. I appreciate it.
 
Mihylo33

Mihylo33

Some of us have been around when that bike was sold as new. 82/83 is my guess as well. However it's hard to tell if it's a yamaha by the pic you provided. On my phone it looks like an 84/85 Suzuki rm80. I'm sure it's a yamaha tho.

Clean that carb two times and then clean it once more. I'm sure you have some plugged circuits in there. Also check the topend compression like Steve said. Chances are you need a piston and rings.
 
2strokesteve89

2strokesteve89

RichyRich23:
How was you able to tell what year it was? Okay I'll check the compression tomorrow, Im cleaning the carb tomorrow. Im pretty sure I get one off eBay. Thanks for the help. I appreciate it.
Click to expand...

82 is the first year for liquid cool on the 80 and the only year the radiator was mounted above the fender, from 83 on the radiator was moved to the frame pretty much where they still mount it today.
 
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RichyRich23

Thanks for the help guys, the compressions low, so I'm ordering a complete new top end and I'll be cleaning the carb out. If the top end/ cleaning the carb doesn't fix it what else should I do?? Also when I put the carb on the intake boot the carb and air box boot doesn't line up properly, how could I fix it?? I've been using tape to cover the gap between the two
 
2strokesteve89

2strokesteve89

RichyRich23:
Thanks for the help guys, the compressions low, so I'm ordering a complete new top end and I'll be cleaning the carb out. If the top end/ cleaning the carb doesn't fix it what else should I do?? Also when I put the carb on the intake boot the carb and air box boot doesn't line up properly, how could I fix it?? I've been using tape to cover the gap between the two
Click to expand...
What was your compression test reading? Show me pics of air box to carb also.
 
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Mihylo33

Mihylo33

RichyRich23:
Thanks for the help guys, the compressions low, so I'm ordering a complete new top end and I'll be cleaning the carb out. If the top end/ cleaning the carb doesn't fix it what else should I do?? Also when I put the carb on the intake boot the carb and air box boot doesn't line up properly, how could I fix it?? I've been using tape to cover the gap between the two
Click to expand...


Stop!!!!!
1st you need to pull the current top end to make sure that the cylinder doesn't need to be honed or bored or that itosntobersized already.
Then the rear boot should be able to turn I think.
 
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