PW80 problems.

[fatpastyhead]

Hi people.

Looking for help on this bike i have just bought for my son. 

So i got it back and it was running ok-ish but only with the choke on. So i replaced the non-existent air filter, plug and transmission oil just as a matter of course. 

Then i took him on the track and realised the kill switch assembly which holds the throttle was broke and by this time it was being a pain to start and a bit of a pig to keep running because i had to leave ot on choke. 

Fast forward a week and after talking to a garage and doing lots of google searches(mainly brining up this site) i was convinced i had a dirty carb. Took the carb apart and the float had dents in it and it looked terrible so i went on ebay and ordered and aftermarket one and replaced the kill switch assembly. I also replaced the 2 stroke oil under the seat.

Now the bike is back together and after starting the bike it just runs on full throttle, cant stop it. Also only with the choke on. 

Firstly i am a little worried as I am unsure whether the 2 stroke will have pumped through at this stage and do not want to seize it?

Do these aftermarket carbs need setting up or do they come preset? If the former, how would i go about that?

I also did not use the accelerator needle that came with the carb, i just put the Yamaha 1 straight back in and it seems to slide in and out with no problems. The throttle does not stick at all.

I should also mention the bike starts with no problems at all. 

Any help would be greatly appreciated as i would like to get my lad back down on the track ASAP.

Many thanks

 

[MaybeMe]

Do you have to run the oil injection if you are racing it or what not?

If not, run premix and plug off the oil injection pump with plugs you can buy.

[fatpastyhead]

Yes i still have the oil injection fitted. To be honest I am not comfortable removing it. First bike i have had for him that has it and was hoping to carry on using it. 

Is there any beneficial reasons as to why i should not use it?

 

Cheers

[Myboyblue]

Here’s an example of why one would want to remove the oil injector. My daughter’s PW50 was running like crap until I removed the injector and began running mixed gas 32:1. The bike really woke up.

[MaybeMe]

12 hours ago, fatpastyhead said:

Yes i still have the oil injection fitted. To be honest I am not comfortable removing it. First bike i have had for him that has it and was hoping to carry on using it. 

Is there any beneficial reasons as to why i should not use it?

 

Cheers

Sometimes they run like crap with them still fitted; I’ve heard of some failing and the bike seizing. Just general things that are avoidable by not having it. Like stated above, it can run much better running on the optimal premix ratio.

[fatpastyhead]

So being a little paranoid and taking into consideration what you guys said I decided to put clear line in from the oil injector so I could see it going in. I wasn't really comfortable removing it.

As for the bike running the way it was, that was purely my fault for not changing the accelerator needle assembly. They looked the same at the time so perhaps a mixture of the beer and not enough light in the garage(oops).

Just in case anyone else gets this replacement pw80 carb and gets a little stuck like me then here is what I learnt:

- No.1  on the image posted is for your oil injector. This bit of pipe will need to be extended as the barbed intake is at an angle and requires a slightly longer piece of tubing. I used clear so I could see the oil going in.

- No.2 & No.3 on the image posted are overflows and both require some overflow tubing. I used the same clear tubing I used for my oil injection.

- After speaking to the guys I purchased the carb from, they told me it comes set up for a PW80 and should not have to be adjusted. Mine was no exception. It now runs and idles great.

- You must change the accelerator needle that goes into the carb otherwise the bike just revs high and has no control.

Hopefully this is of some help to some people that were stuck like me.

Thanks to the posters above. I think once I am a little more comfortable with knowing the bike I may take out the oil injection. Simply because I do not trust it and do not want a seized bike.

??

- 

 

[MaybeMe]

3 hours ago, fatpastyhead said:

So being a little paranoid and taking into consideration what you guys said I decided to put clear line in from the oil injector so I could see it going in. I wasn't really comfortable removing it.

As for the bike running the way it was, that was purely my fault for not changing the accelerator needle assembly. They looked the same at the time so perhaps a mixture of the beer and not enough light in the garage(oops).

Just in case anyone else gets this replacement pw80 carb and gets a little stuck like me then here is what I learnt:

- No.1  on the image posted is for your oil injector. This bit of pipe will need to be extended as the barbed intake is at an angle and requires a slightly longer piece of tubing. I used clear so I could see the oil going in.

- No.2 & No.3 on the image posted are overflows and both require some overflow tubing. I used the same clear tubing I used for my oil injection.

- After speaking to the guys I purchased the carb from, they told me it comes set up for a PW80 and should not have to be adjusted. Mine was no exception. It now runs and idles great.

- You must change the accelerator needle that goes into the carb otherwise the bike just revs high and has no control.

Hopefully this is of some help to some people that were stuck like me.

Thanks to the posters above. I think once I am a little more comfortable with knowing the bike I may take out the oil injection. Simply because I do not trust it and do not want a seized bike.

??

- 

 

Very informative, nice write up!

I hope to get one of the 50s for my daughter when she’s old enough, and if she’s into it haha. Hopefully she likes blue!

[fatpastyhead]

18 hours ago, MaybeMe said:

Very informative, nice write up!

I hope to get one of the 50s for my daughter when she’s old enough, and if she’s into it haha. Hopefully she likes blue!

I think they made the older ones in pink and white so it may be possible to buy aftermarket fairing and change it up a bit for her. I have just purchased a new set of plastics for my sons bike. Once he stops falling off i will out them on haha.

 

The PW50, in my opinion is the best starter bike out there. So many people have them at the track we go to. Great little machines.

[fatpastyhead]

NoI have another quick question if anyone could help? I didn't want to open a new thread as this was already here.

The bike seems to give off a bit of white smoke and I am wandering if this is normal?

I have a feeling the petrol i used still has some premix oil in it from my sons old bike so I am guessing this would cause smoke? But I was thinking that would be blue?

She starts perfect and idles perfect but I still worry about the smoke due to not having enough knowledge on these bikes. 

Thanks

[MaybeMe]

3 hours ago, fatpastyhead said:

NoI have another quick question if anyone could help? I didn't want to open a new thread as this was already here.

The bike seems to give off a bit of white smoke and I am wandering if this is normal?

I have a feeling the petrol i used still has some premix oil in it from my sons old bike so I am guessing this would cause smoke? But I was thinking that would be blue?

She starts perfect and idles perfect but I still worry about the smoke due to not having enough knowledge on these bikes. 

Thanks

Is it white or grey?

White is water. Could be condensation in the pipe, no radiators or head gasket to leak.

Does the smoke smell? It’ll either smell like burning oil or the classic premix smell. Each one is pretty distinctive.

[fatpastyhead]

21 hours ago, MaybeMe said:

Is it white or grey?

White is water. Could be condensation in the pipe, no radiators or head gasket to leak.

Does the smoke smell? It’ll either smell like burning oil or the classic premix smell. Each one is pretty distinctive.

I have oil in the fuel as well as oil from the oil injection so i  am guessing it is that?

I will dump the fuel thats in it and put fresh stuff in. 

[MaybeMe]

11 hours ago, fatpastyhead said:

I have oil in the fuel as well as oil from the oil injection so i  am guessing it is that?

I will dump the fuel thats in it and put fresh stuff in. 

It couldn’t really be anything else. If it were tranny oil, then the cases haven’t been mated correctly and it would seep through to the crank and burn off. But that’s unlikely unless the case was damaged.

Maybe from washing it? I would be more concerned with fouling plugs with the premix and oil injection running.

[fatpastyhead]

2 hours ago, MaybeMe said:

It couldn’t really be anything else. If it were tranny oil, then the cases haven’t been mated correctly and it would seep through to the crank and burn off. But that’s unlikely unless the case was damaged.

Maybe from washing it? I would be more concerned with fouling plugs with the premix and oil injection running.

Casing doesn't look damaged. That was my initial thought, perhaps the crank seal was leaking but it doesn't appear to have lost any oil.

I will dump the fuel thats in it and but a couple spare plugs for the weekend and see how it goes. 

There is a part of me that wishes i had removed the oil injection now and just used premix haha.

[Spooge]

Run it!  It's a two-stroke, they burn a little oil by design, so no worries.  Your in the UK, a cool, humid place so you are more likely to see it.  Two strokes use gas mixed with oil for ring seal, cylinder, and crank bearing lubrication.  Get the youngster out there and let 'em rip.    

[Spooge]

On 12/5/2017 at 4:45 PM, fatpastyhead said:

I have oil in the fuel as well as oil from the oil injection so i  am guessing it is that?

I will dump the fuel thats in it and put fresh stuff in. 

You need to either pre-mix your fuel (put oil in the gas) or use the oil injection system.  If you chose to pre-mix, remove the oil injection system and block it off.  If you chose to use the oil injection system, do not add oil to your gasoline.