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I have a very old 10 plus years old 49cc pocket bike with a bit of an issue. my pull start rope broke so I removed the pull start housing and decided to use my cordless drill on that center nut to start the bike it actually worked. I also decided to use my electric impact version of the same tool and oops i probably shouldn't have done that oh well you live and you learn. broke the bolt that the nut was on right off. to fix the issue I decided why not weld that nut back on. maybe I'm a little crazy here with my ideas but what do you think was the bolt easy to replace? should I have just done that? also I don't even use the electric start on this engine such a pain with battery charging issues. should I remove the electric start? but if I do that would the pull start stick out far enough for me to use the pull starter?
 

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Crap man the shank bolt supper hard to find... The problem is once you take that starter armature off you're going to have the end of the crankshaft with just a taperd keyd nub with no way to really bolt starter cage to the one without the electric start has a adapter piece that makes it work I have seen guys machine down the starter armature and make an adapter but that takes work and tooling it would be best to try and find the shank bolt before the glue that holds the starter armature let's go and the whole thing falls apart on you... Here is a picture of the shank bolt.


Edit - I found a shank bolt on eBay normally I wouldn't paste the link but for this hard to find part I'm going to do it...

https://www.ebay.com/itm/Starter-Pa...cc-and-49cc-Scooters-and-Pocket-/163735403491
 

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Hey thanks man! Yeah that’s it alright. You don’t think that weld is likely to hold very long ha? I felt like another issue was even if I had a new bolt I would have to extract the the old one out. How would I even get access to the rest of that bolt. What are the parts that I would have to remove to get access to the tip of the bolt to extract it?
 

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That link didn’t take me to a particular thread it took me to a list of threads.
 

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Because I'm using the mobile version...

You're going to have to go up and paste this into the search box

Pawl Claw Bolt BROKEn HELP PLEASE!!!
 

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Because I'm using the mobile version...

You're going to have to go up and paste this into the search box

Pawl Claw Bolt BROKEn HELP PLEASE!!!

Here is an update. So I got the Pawl Bolt that was broken off welded on and I have my fingers crossed that it holds. I started the bike about a dozen times since then and it seems to be pretty solid. For now I think I’m just gonna role with that.

Here is a problem that I have been noticing sorry off topic. When I turn the bike off there is a very slow drip of fuel that comes from the carb and out the air filter. The carb is new and is performing great but this slow flow of fuel builds a pool at the bottom of the pocket bike body kit. Do I need a fuel shut off valve? Is this one a good one to go with or is there one that you think you like more?

If the link doesn’t open please just copy and paste :)

https://www.ebay.com/itm/392384557749

Attached a pic below as well.
 

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It will work but there is defentley something wrong with that Carby I whould just replace it
 

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It will work but there is defentley something wrong with that Carby I whould just replace it

Ah so it is the Carburetors job to stop the flow of fuel as well ha?

Darn it I just got it a week ago and it does make the bike run well. This is the one I got.

https://www.ebay.com/itm/282012015163

Do you think these Chinese built carbs are a big waste of money?

Maybe I should just rebuild the old Walbro wt603a.
 

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The trick to the pumper carbys is

1. Always use ethanol free fuel mixed with some fuel stabilizer.

2. Keep everything sterile and free of dirt I have a certain gas can that I use that's really clean just for my pocket bikes and it's good practice to clean the gas cap and around the gas can lid before you open them with a clean rag.

3. Use a premium fuel filter the kind that are designed for chainsaws and weed eaters and are able to deal with two stroke fuel.

More then likely there is some dirt under the seat or the seat is defective there is a tiny screen inside the Carby it's basically worthless.
 

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See i did the same thing with a impact drill on the pawl bolt and i was wondering if i could fit a short bolt to hold the pawl to the Armature would it actually work.
 

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The shank bolt goes through the starter the end of the starter that fits into the crank is taperd they all so use glue to keep it from spinning on the crank so if the shank bolt gets twisted off then all you have is the press/glue holding it together and the shaft of the shank bolt holding it center it might hold forever then again the glue can let go and it will fall apart and you won't be able to start the bike

The Chinese use soft steal to make the bolts for these things they shouldn't be drill started ( like you can get away with on Stihl and Brigs stuff)

Unfortunately parts are starting to get scarce and we really do need member's to start parting out engines that are worn out or not wanted instead of throwing them in a box to be forgotten about or in the trash...
 

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Discussion Starter #14
The trick to the pumper carbys is

1. Always use ethanol free fuel mixed with some fuel stabilizer.

2. Keep everything sterile and free of dirt I have a certain gas can that I use that's really clean just for my pocket bikes and it's good practice to clean the gas cap and around the gas can lid before you open them with a clean rag.

3. Use a premium fuel filter the kind that are designed for chainsaws and weed eaters and are able to deal with two stroke fuel.

More then likely there is some dirt under the seat or the seat is defective there is a tiny screen inside the Carby it's basically worthless.

I thought all gas stations sold gas with ethanol in it. Where do you buy your ethanol free gas?

Is this stabilizer ok? Do you make your mix as described on the bottle or make it stronger?
 

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Here some gas stations sell ethanol free premium if your state doesn't have ethanol free then you can get it in cans at Home Depot or Lowe's or use that stuff you pictured per the directions on the bottle to help counter the effects of ethanol in the fuel ( the ethanol hardens the seals inside the carburetor and makes it fail) fuel stabilizer helps keep the fuel fresh I allso add octane booster to bring it up to at least 95
 

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Discussion Starter #16
ok So I gave up on that rotary style Chinese built carburetor and pull out the old Walbro Wt-603 and guess what fuel was flowing through the carburetor air filter also. Ok so I took it apart and looked for dirt anywhere specially under the seat that you described(looking for clues as to what the seat could be). Anyways I find some videos about the metering pin and lever and start messing with that. I took the pin out and cleaned inside and around it with carb cleaner and blew some compressed air throughout the carburetor. Put everything back together and fuel is still leaking through the air filter.

Is that meter lever and pin w/spring what is responsible for stopping the flow of fuel?

Dave’s Motors mentioned that there is variable success with carb rebuild kits and at $38 I can get a new Walbro wt-668.

Is the existing wt-603 That I own worth rebuilding or should I just go with the wt-668?

Is there going to be an end to this problem? Lol!

Thank you!
 

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I don't think the wt603s pulse port will line up with the stock manifold dont you have to buy an adapter manifold to make it work???

I'm all for the 20$ weed whacker carburetor they'll last me about two years using fuel stabilizers and ethanol fuel treatment or ethanol-free fuels and high-quality two stroke fuel friendly chainsaw style fuel filters.

most people have the same results with pumper carburetors you can either replace the China one's for $20 or you can waste money and time rebuilding expensive carburetors it's all up to how you want to do it!!!
 

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Discussion Starter #18 (Edited)
I don't think the wt603s pulse port will line up with the stock manifold dont you have to buy an adapter manifold to make it work???

I'm all for the 20$ weed whacker carburetor they'll last me about two years using fuel stabilizers and ethanol fuel treatment or ethanol-free fuels and high-quality two stroke fuel friendly chainsaw style fuel filters.

most people have the same results with pumper carburetors you can either replace the China one's for $20 or you can waste money and time rebuilding expensive carburetors it's all up to how you want to do it!!!

The Wt-603’s pulse port did line up fine with the stock manifold. That thing ran reliably for a long time actually. I’ll have to check and see if the wt-668 pulse port is the same before purchasing.

“20$ weed whacker carburetor” can you elaborate which $20 carburetors you are referring to? Where do you purchase those?
 

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Discussion Starter #20 (Edited)
Just goto Amazon or eBay and typ in 49cc carburetor or pocket bike carburetor

Thanks for clarifying Mr. Kitty :)

Ok here is an update. I pulled out a carburetor just like the one you’re recommending and for whatever reason it fired right up and wasn’t leaking. Go figure! It was leaking just a couple days ago and now it’s not leaking and it fired right up and held an idle too. So I took it for a nice long drive and the bike was pulling nice on WOT and all of the sudden I started to hear grinding. The bike died and when I went to pull start it it was all grinding. Walked the bike back home to open it up and found that the electric starter armature was no longer pressed on and it had come loose and the inside had grinded all up. It just popped right off which exposed the broken starter pawl bolt remember that bolt? I was able to back that broken bolt out and here is a pic of it in my hand in the first pic. So that’s one problem and the second problem is that two of the points that the engine was mounted to had broken off. The second pic shows the left mount point and the third pic shows the right side mount point that I had previously modified because it had broken before a while back.

So at this point Mr. Kitty what do I do? Are the broken parts worth replacing?
 

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