Eric B's advice on Yamaha PW80

[PerniciousBill]

I bought my grandson a chinese knockoff of the Yamaha PW80 and couldn't get
it to run right. The carburater would load up, and tho it ran awfully rich, it
would run fine until you tried to give it full throttle, then it would sputter,
and refuse to rev up. Many people posted on google that the motor had a "rev
limiter" in it, and to just accept the pw80s as a great little trainer bike.
After following Eric B's advice on how to tweak the PW80, the neighbor boy,
age 15, likes riding my grandsons pw80 clone, better then his own Yamaha YZ 85.
In his words about the pw80, "It's a beast!!!"
Once again, my sincerest thanks to Eric B. He has made that grandson of mine
awfully happy.
Sincerely,
Buck Parker

[Eric B]

PerniciousBill wrote:

Glad I can help! Now, keep in mind that your grandson will soon start
pounding the s*&t out of it;-) Checking the swingarm bolt, and the motor
mount bolts are a daily must do--they will come loose with jumping. Have
fun!

Eric
--
Eric B-there are too damn many Erics here!
2000 XR250, '74 Elsinore MR50 (original owner),
'99 CR80 (11yr old daughter), '96 RM80 (14yr old son), 2000 DS80 (visiting
kids).
Remove "nospam" from reply-to

[rod richeson]

Eric B wrote:
> PerniciousBill wrote:
>
>
>> I bought my grandson a chinese knockoff of the Yamaha PW80 and couldn't
>> get
>>it to run right. The carburater would load up, and tho it ran awfully
>>rich, it would run fine until you tried to give it full throttle, then it
>>would sputter,
>>and refuse to rev up. Many people posted on google that the motor had a
>>"rev limiter" in it, and to just accept the pw80s as a great little
>>trainer bike.
>> After following Eric B's advice on how to tweak the PW80, the neighbor
>> boy,
>>age 15, likes riding my grandsons pw80 clone, better then his own Yamaha
>>YZ 85. In his words about the pw80, "It's a beast!!!"
>> Once again, my sincerest thanks to Eric B. He has made that grandson of
>> mine
>>awfully happy.
>>Sincerely,
>>Buck Parker
>>
>
> Glad I can help! Now, keep in mind that your grandson will soon start
> pounding the s*&t out of it;-) Checking the swingarm bolt, and the motor
> mount bolts are a daily must do--they will come loose with jumping. Have
> fun!
>
> Eric

I musta mist that thread, please repost your "tricks" so I can make my
daughters a little better/faster...

Thanks,
Rod

[PerniciousBill]

Rod, here is Eric B's advice from a thread posted to this group back in august
to a question Brian Colbert asked. I just copied and pasted Erics response
here.
<Brian Colbert wrote:

> Hi,
>
> I have a 2001 Yamaha PW 80 for my youngest boy. It has starts when cold
> pretty easily, but once it is ran for a short while, it stops running.
> Like
> it is starving for gas or possibly being flooded.

Which is it? Pull the plug, if it's black and sooty, it's rich, if it's
nearly white, it's lean. Did you buy the bike new or used? Have you ever
cleaned the filter? Did you check to make sure it had one? Does the
condition worsten or improve with the choke on? Have you cleaned the carb?

>When it cools back
> down,
> it will do the same thing after running for a short time. This short time
> is about the time it takes to travel the length of one block.
>
> Does anyone have any suggestions for me?

PW80's come horribly rich from the dealer, at 4500 ft fuel practically
pours out the pipe. The smart money is on that being your problem. Check
the plug, if as above (black and sooty) do the following standard PW80
tweaks:

Make sure you've got the spacer out of the exhaust-just a washer between
the pipe and cylinder.

Make sure the filter is clean and oiled-and the airbox.

Remove the snorker from the airbox.

Drill holes in the back of the airbox-DO NOT DRILL where air will bypass
filter.

DO NOT tinker with the oil injector-the most common error on these bikes is
the assumption that a rich condition can be fixed by reducing the injector
output- this is wrong. The less oil you have being injected, the richer
the bike will run, exacerbating your problem even more. The factory
settings are fine, leave 'em be.

You can fine tune from here for your climate/altitude with jetting, with
the airbox opened up the factory jetting is spot on for 4500ft from about
85 to 95 degrees in low humidity.

With nothing but the above mods (and racing without the slencer-but that
was left on for trails) and factory jetting, my daughter earned about a
dozen trophies the year she was on a PW80 racing the mini playbike class
(100cc and under playbikes).

Good luck!

Eric