Report on PW80 modifactions

[KawieKX125]

Just finished the modifications to my PW big wheel 80. It turned out pretty well.
I installed/did
-Boyesen reeds
-New top end
-UNI pod filer, eliminated airbox
-Removed exhaust restrictions
-Got rid of oil injector
-Raised front end with spring spacers
-Redrilled rear shock mount to raise rear end
-Pro Taper xr50 bars
-Removed Kickstand
-Smaller front sprocket

I also did the clutch mod with removing balls, but it didn't do anything at all, just made the clutch slip. The bike is a ton faster and much more responsive, but not as fast as I had hoped. FMF said their pipe will not fit the bike, so I am out of luck for a pipe.
I think when the top end is shot again me and my friend might do a custom big bore and stroker hehehe. He works for a yamaha dealer and all the parts for the bike cost a whopping 110 dollars!

 

[_BudMan]

Thats great I just did a few mods to my boys.
-removed exhaust restrickors
-changed rear sprocket 15/45
the gearing is working great I have a one acre lot not to house and he's now able to get third.and the bike will wheelie in first and second.
next I have to get a couple loads of dirt to put in some hills mild enough for him to roll over but steep enough so when i hit them with the f7 it will launch.
I seen a cdi at trinity racing web sight that removes rev limiter and hottens spark
Its for kasea 90 quad 82cc ,5 wire system like the pws I have been meaning to call the
I have to make sure that will work before I get a pipe and he has to get better at his up and down shifting.maybe a next winter project .open up exhaust port a hair and good Polish .double base gasket and play with port timing.

 

[Jasle]

get ahold of the ignition of an early eighties pw80. I think 85 or older and they rev limiter is not on them. have the yam dealer go back and see when the part number changed and then get the older one.

 

[KawieKX125]

Already done, the bike is old enough not to have a rev limiter, it is a 96 and from everything I understand, the bikes older than 94 are rev limiter free.

 

[scairns]

Mods

What do you have too do to eliminate the oil injector ?

Did you replace the throtle cable or just diconnect at the joint ?

Any other tips ?

Thanks !

PW80 Dad

 

[scairns]

40:1 mixture ?

Once the oil injection is removed or disabled, will I have too rejet to run 40:1 (my mix) ? Not sure what the injector runs.


Thanks !

 

[Jasle]

Probably. The injector usually has more than 40:1 oil.

 

[wasted]

this is something I did to my sons that seemed to work pretty good...
I cut the spark arrestor out along with all the other exhaust restrictions and it helped but made it quite a bit loader, and seeing as I wasnt real impressed with the how the core of the silencer was made to begin with I cut the solid core out and made a straight through packed core with some heavy galvinized wire mesh and extra packing I had... it kept the extra power up, quieted it down quite a bit, and made it sound more like a little mx bike than what it sounded like before...

just something for the "tinkerers" to think about... :thumb: