Hensim 149cc 4 Stroke Not Running/Idling
 

Hey guys, I was looking for some advice on what I should do to get my dirtbike running again. I recently purchased my 149cc bike and it won't start or stay on really. I have to spray gas into the carb for it to kick over at all and it dies almost immediately. I'm unfamiliar with the larger carbs of dirtbikes and 4 stroke motors in general. I'm used to working on smaller 2 stroke motors (typically gas trimmers). The carburetor is a PD11 Sheng Wey. I've already cleaned out the carb several times with carb cleaner. I take out all of the jets and use compressed air to blow out any debris and sprayed them with carb cleaner. I cleaned the outside and took my time making sure all the debris on any metal surface is cleared out. I wasn't able to remove the float because I don't know how to take the pin out safely but I tried to level the float and make it parallel with the carb body as best I can while its sitting upright. I'm suspicious of some kind of debris in the fuel tank that's not allowing the carb to get fuel. Can anyone share some advice with me on how to get my bike running again? :hmm:

Thank you

http://i.imgur.com/wSxqGVG.jpg

http://www.ccwthariders.com/uploads/...ing_manual.pdf worth reading
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My advice is thrown that Sheng Wey (this Taiwanese brand are infamous for their weirdo jets that can't find elsewhere) to the bin & get a Mikuni or Keihin clone are proven by others...

Figure out what carb RPS imports the newer version of the bike with. The Viper 150 made by Haosen is really and truly a continuation of the Hensim company. If you click on parts, they show a photo of a carb, but do not specify which one it is. Once you find out the carb, go on Ebay and order one there (or order one from RPS).

http://www.therps.net/DB-Viper.html

According to http://mefast.com/Hensim/DirtBike/15..._Dirtbike.html the engine is known by chinese as "CG150" ...
http://blogimg.goo.ne.jp/user_image/...a72c3b9f91.jpg
PZ27 (Keihin clone) is de facto for these by chinese bike industry... Some sh**head just jam the PZ26 in there which the result = VERY LEAN
http://www.youtube.com/watch?v=2Y-R_1KOo38
~6:30

1 of the tricks https://translate.googleusercontent....Cst8CzVJMnCmYQ when somthing went wrong...

So I ordered a new carb for my zongshen 125 but the throttle cable was too short so I threw it on my hensim and it started right up! It seems like the bike is not very responsive to the throttle, it has a 1 to 2 second delay when I throttle it before it actually speeds up. What can I do to fix this? The carb is a pz30

Which carb did you order? Can you show us a link?

NIMTEK 30mm PZ30 Carburetor Carb Lever Choke Pit Dirt Bike ATV Scooter Moped 150 200 250 300 cc https://www.amazon.com/dp/B01ALAKET0..._p.lsybB0FPJRD
Should I not be running this carb? Bad for the motor?

If it's a Pz30 (ie. for a larger displacement) then ALL stock setting are wrong... Try tricks to make it right again ...
Mixture screw <pilot jet> / Different position <Needle clip>/
<main jet> If Sheng Wey is same shape & ~9?, swap it in... If not put hair size copper wire(s) from some spare electrical cable. Need some calculation... Don't know what's available from ur side BUT ⌀0.12mm varitey is quite common here Example: http://www.ebay.com/itm/262157657988 [Learnt from folks travel to higher altitude] OR proper smaller jet...

I will make some adjustments to the bike tomorrow and post my results. Thank you!

If you can't find a smaller main jet, you can clean it, fill it with solder and then drill it to whatever size you wish. The numbers on a jet generally refer to mm diameter, so a 100 is 1.00mm. Let's say you wanted to try a 95 jet; ask Google what the inch conversion is (it's 0.0394") and then look that up on a drill chart to determine the drill bit number size (it's a #61 or #60). Carefully drill out the jet to that size and give it a try. It takes lots of experimentation, but you'll eventually nail it. Be sure to write the size on the bowl with a Sharpie each time, so you don't lose track.

Very nice idea. I've been busy this week but I should have time to fiddle with the bike on Sunday... I'll post back here then.

Thank you guys for the help I appreciate other people sharing knowledge with me !

More detail http://www.chinariders.net/showthrea...897#post194897 of that trick...

I put in the old jet from the old carb, it started right up and I rode the bike maybe a mile around my neighborhood topping out at 30 mph maybe. I come back 5 mins later and now it won't idle at all. It turns on for half a second and then shuts off

Edit : okay I put the other jet back and just took the little top part of it in the new carb and it started up. I'm trying to adjust the mixture screw which adjusts fuel as far as I know. I was able to turn the screw all the way in and it still idled... I can find no adjustment with it from 3 1/2 turns out (which is where it sounds like it will die) and turned all the way in where it doesn't start to die if I pull the throttle open quickly. What does this mean?

I think the slow jet is too small.

So I got a keihin pz27 carb for the bike, according to the chart earlier posted by humanbeing. The bike doesn't start now, so I started taking it apart on the side and the cover for the magnet and sprocket has a gasket that came apart. So before I use gasket maker to seal it again, is there anything else I can try before putting it back together and selling it as is? I don't want to give up on this bike but it seems like im in over my head :hmm:.

I want to check if cam timing and valve clearance is ok but I don't know how to do either (just possible solutions I found while researching), there are no videos of anyone with hensim 150 or viper 150 online and I don't know much about bikes