139qmb Stroker Crank Discussion

[larry001964]

Before any body starts this project know it's VERY VERY EXPENSIVE !!!

Hey guys here's my stroker parts list, I have put this together
so that anybody trying this build can consolidate shipping cost
and save money... I will include only the parts I feel are absolutely
necessary.. Hopefully people can start building a kit around this and bring down the cost... At least that's my hope.

Parts For Scooters
Hoca Stroker Crankshaft
Hoca Hi Performance fan
Timing chain

Scrappydogscooters.
Oil Pump
Oil Pump Gear
New Intake studs
New exaust Studs
Free Flow Exaust
Final Drive Gears. 17/49

Enviromoto
NCY 85 cc BBK "52"mm
NCY HP Cam
NCY Big Bore Head
Engine Gasket Set
Oil Seal Kit
50 mm bbk Top end gasket kit.

Mainepeace
20mm carb
Hoca Tranny Kit Variator no larger than 87mm ( Use all but Contra Spring ) Stroker power curve is different..
Dr. Pulley sliders 1 set 7 grams 1 set 8 grams. ( depending on your weight you may have to mix these to get the best performance ). Will also need to cut vent holes in CVT cover..
Gates Premium drive belt.
Variator Fan
Tail Light LED ( made a big difference starting it )
Turn Signals LED ( made a big difference starting it )

Jetsrus
98, 100, 102, 105 main

Napa Machine Shop
Pressed old oil pump gear off crank and put new gear on
Pressed the old final drive gear off to put on the newer one

Smiths Farm supply and hardware,
bolts, Nuts, and washers..

Batterystuff.com
YTZ14S 12v AGM Maintenance Free Powersport and Motorcycle
Battery 230 cca 11.2 Amp.

Autozone
Oil
Degreaser
carb Cleaner
Spark Plug NGK
4 awg battery cables

Adventurous Scooters
Hotter Orange Coil.

motorcycle-superstore.com
Pirelli SL 26 Performance Front/Rear Tire's

[larry001964]

Man guy's and gals I spoke too soon thinking I had the problems fixed.
Your not going to believe this, I was running 6.5 grand on my tack coming home from work Friday, decided to mix my sliders 7 and 8 grams.. opened up the variator and it's tearing this one up... The plastic guides one is broken, and I have a couple gouges in the fingers above the rim of the variator...

I'm so dissapointed, Tore up a NCY and a Hoca.. It's still drivable but how much longer it will hold up is anybody's guess.. Not sure what to do next ? modify a 150 variator ? custom made boss ? and turn it down to 87 mm ? wish I had a metal lathe...

I'm totally at a loss...

[Deleted]

pictures?

[Deleted]

the plastic guides you used did they come with the sliders? mine came with Motori Tec ones.

[larry001964]

Mar 18, 2012 15:49:13 GMT -5 stroker said:

pictures?

Hi Fast
Here's the picts of the damage, I didn't get any plastic guides with my sliders, I used the ones that came with the Hoca tranny kit..






I'm totally at a loss, only 160 miles on this.. The plastic guides are the first to let go then comes the damage to the variator. Can't really say how disgusted I em right this moment... Looks like the forward stress on the backing plate, is pushing the plastic guide against the aluminum finger guides and is cutting the plastic guides in half..

[Deleted]

those look like stock ones..autotech355 sends out Motori Tec guides with his sliders..i have never seen just the guides for sale though

www.ebay.com/itm/330678907990?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1439.l2649#ht_1282wt_870

[larry001964]

Are the Motori Tec guides made of a better plastic ?

[Deleted]

they are bigger..and i assume better plastic.

[Deleted]

i have seen the stock ones break like that on a true 50cc....you need some better quality ones is all IMO

[larry001964]

Mar 18, 2012 17:34:23 GMT -5 stroker said:

they are bigger..and i assume better plastic.

The more I look at this the more I'm convinced it's the guides that are failing and causing this. I'm wondering if i can adapt the guides from a 2 stroke, Ive been comparing the variators. some are 90 cc and about the same size variator, so I'm thinking they must be experiencing the same stresses if not more..

[Deleted]

yeah im looking at those too..and that was my thought also.

[Deleted]

or maybe a whole variator from a 2t?

[larry001964]

Mar 18, 2012 18:01:30 GMT -5 stroker said:

or maybe a whole variator from a 2t?

My thinking too.. Perhaps the whole variator.. Looks like it would take a few minor mods, maybe a custom boss..

[90GTVert]

I have broken a ton of those guides on my 2Ts... but there's a catch. It's pretty much always when my ramp plate and vari are separating. Put the vari together, don't need the weights, and set it face down with the drive boss in it. Add whatever spacers you use in there, if any, and even try it with the fixed half of the vari to see if it makes a difference. If that ramp plate can pass the guides, it's likely to break them. If you've ever heard me say I've owned multiple Hoca variators... that's basically why. I mod them to the point they separate too far and then break the plastic pieces and then damage the vari itself.

[larry001964]

Mar 18, 2012 18:21:44 GMT -5 90GTVert said:

I have broken a ton of those guides on my 2Ts... but there's a catch. It's pretty much always when my ramp plate and vari are separating. Put the vari together, don't need the weights, and set it face down with the drive boss in it. Add whatever spacers you use in there, if any, and even try it with the fixed half of the vari to see if it makes a difference. If that ramp plate can pass the guides, it's likely to break them. If you've ever heard me say I've owned multiple Hoca variators... that's basically why. I mod them to the point they separate too far and then break the plastic pieces and then damage the vari itself.

Hi Brent, and thanks
Here's a pic of what you said.




I'm wondering if it would not be easier to have the key guides made of a different material, say maybe brass ?