hello,lisa here

lisala433

New Member
Aug 17, 2008
14
0
0
hinton okla.,USA
Hi,
new to all this ,anyone had problems with the pk80 black motor from powerking in canada......pls help....oiling ports in cylinder very rough;shelled rings,piston cyllinder and wrist pin needle bearings in 120 miles.....What's a girl to do...HELP!!
 

Dave31

Moderator
Staff member
Mar 1, 2008
11,204
29
38
Aztlán, Arizona
Welcome Lisa to the forum, glad you joined us :)

I do not have a powerking, I believe a few members here do....what where you running your fuel/oil mixture at?
:bike2:
 

Jemma Hawtrey

New Member
Dec 29, 2007
288
2
0
Essex, UK
the deep scoring on the piston and cylinder walls was at the 2 oiling ports in the cylinder
If you are running a 16:1 mix then it shouldnt be anything to do with the mixture. Have you checked the colour of the spark plug - anything grey or white means overheating - you need a nice tan/brown colour. Running a two stroke lean will quickly kill a motor.

Since you have done such a small mileage it might be worth talking to the supplier because it sounds like fault in the motor.

define what you mean by 'rough' - if there is scoring on the inside of the cylinder then it might be from the rings or something being wrongly installed inside the engine. I assume by the term 'shelled' you mean broken?

glad to see you on the forum :)

Jemma xx
 

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
2,605
2
38
68
pampa texas
welcome to the foum.
sounds like you might have gotten a lemon contact the seller and see if they can send you a new one or replacement parts.
Your in Ok. I'm 3 hours due west of Ok. city keep on here and ask questions with pictures if you can we might be able to help.
If the cylinder is scored you will at least need gaskets, cylinder,piston with rings and needle bearing and wrist pin with the keepers. Don't know what happened to your engine but like I said if its new contact the seller and see what they can or will do to help.
I went back and reread your post sounds like the wrist pin needle bearings let go or the circlip wasn't installed and may have went through the engine tearing you know what out of it. Do contact the seller
Norman
 
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lisala433

New Member
Aug 17, 2008
14
0
0
hinton okla.,USA
Thanks All for the quick replys;to jemma plug was light chocolate,shelled="Destroyed!!"...lol...made horrible rattling sound,just before it quit...
Wrist pin rings were still intact and tight....,"Lord Vader",wrist pin needle roller cage was broken in peices....intake and exhaust ports were smooth,oiling ports for lower crankcase were really rough.....rod has several thousandths side play now.....would you all rebuild with new top end or scrap ??; thank you sooooooo much........Lisa
 

Jemma Hawtrey

New Member
Dec 29, 2007
288
2
0
Essex, UK
Thanks All for the quick replys;to jemma plug was light chocolate,shelled="Destroyed!!"...lol...made horrible rattling sound,just before it quit...
Wrist pin rings were still intact and tight....,"Lord Vader",wrist pin needle roller cage was broken in peices....intake and exhaust ports were smooth,oiling ports for lower crankcase were really rough.....rod has several thousandths side play now.....would you all rebuild with new top end or scrap ??; thank you sooooooo much........Lisa
So basically the bearings have toasted themselves and taken most of the rest with them...

It depends on your budget I guess - work out what will be cheaper to do and assuming you have the skills and the required equipment a rebuild is possible.

Personally I would contact the seller and get them to send you a replacement or the required parts for a rebuild at the very least.

Can I ask - did the engine run out of fuel by any chance?

This is one of the reasons I stand by the commercial engines such as tanaka - because you have a backup and guarantee on the motor from the manufacturer.

Good luck with fixing it up

Jemma xx
 

Jemma Hawtrey

New Member
Dec 29, 2007
288
2
0
Essex, UK
Thanks Jemma,
Nope was running fine actually,was road testing a new mikuni 18mm carb my boyfriend installed...sounded great but a little short on torque,mid range was great....was testing on highway up and down 30degree hills at about 20mph...power was down a little from the chinese carb....lisa
Now things start to become clear... it sounds as if the new carb was running the engine lean enough to damage it but not lean enough to wreck it immediately... more breathing would mean more power, but if the engine was down on power it sounds like it could be running lean - the plug wouldnt show this immediately... it might even be that you were getting blowby from the carb or gaskets to air - which would make the engine run lean as well.. Would I be right in guessing that it gave up and started sounding rough when you'd opened it up to full speed?

What I do before I make a major change is take the plug out of the motor and clean it off gently with a brass wire brush in the dremel I have. This means that I effectively have a clean/new plug. The idea being that if its showing as running lean after my test road, then I have done 1 mile or so and know theres a problem not 5 miles and only know theres an issue when I hear a large expensive bang somewhere in the area of my right buttock..

With the tuned pipe I have the engine is much stronger on midrange, a little lower off the powerband but will wind out to 35mph on the flat now (which is 10% beyond the manufacturers stock speed. I have been checking its not running lean and it isnt :).

hope that helped :)

Jemma xx
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
236
63
up north now
If you scored the cylinder, it's history...or "herstory". The are nikasil type "liners" and once scored, the make good toast.

Welcome to the forum.
 

Jemma Hawtrey

New Member
Dec 29, 2007
288
2
0
Essex, UK
It looks like you are going to need a new motor..

re the 18mm carb - you will be able to use it on the new motor with the following provisos..

1. run the engine in on the standard carb - details on how to do that can be found on the forum.

2. when you do fit up the new carb/intake use gasket sealant to make sure there are no airleaks (air leak means lean condition)

3. You will have to run the mikuni carb richer so you might need to change jets to make it work. Richer means a bigger jet - leaner is vice versa. There may also be a adjustable clip on the carb to adjust mixture as well as there is on the CIF engines. DO NOT run the engine at speeds where it starts to sound rough - if it does that at high end then you need to go richer on mixture.

To get the best performance out of the motor (after it is run in) get hold of a tuned pipe for your size engine - combined with the Mikuni carb that will give you the best performance.

hope that helped.

Jemma xx
 

lisala433

New Member
Aug 17, 2008
14
0
0
hinton okla.,USA
Thanks so much,Jemma you,ve been such an asset...will do...I may go with Dax this round...am sending pics to powerking,says they will evaluate damage so,who knows thanks again...lisa
 

Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
2,605
2
38
68
pampa texas
Lisa
I hope they will make it good for you as it sounds like your engine took a death hit bearing parts going through the insides will sometimes eat the main bearing and rods big end bearing at the very least it can ding them.
Keep us informed and don't be afraid to PM anyone of us or me if you need to we are here to help. Jemma is doing good I think on helping you with info, its nice to see women involved in the motorized biking sport.
Norman
 

lisala433

New Member
Aug 17, 2008
14
0
0
hinton okla.,USA
Here are a few pics of the motor i inquired about ....will let ya'll know how it turns out thanks everyone...lisa

p.s. there is basically nothing left of the needle roller upper rod bearing to show...it's ground up in peices in the bottom end
 

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Norman

LORD VADER Moderator
Staff member
Jan 16, 2008
2,605
2
38
68
pampa texas
that isn't big enough for a boat anchor but that is what you've got since the bearing let go. the bearing on the crank probably took a hit as well time for a new engine.