Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on Jun 19, 2014 9:35:38 GMT -6
after looking and looking I finally found my answer,
The longer of the two is a Keihin 21 series jet. The shorter is a 26 series. I found on many motor cycle forums that they are considered interchangeable by most users/riders.
After looking at a few more carbs that I had on the shelf and on friends bikes, It appears that the stock carbs that came with the bikes all had a 26 series slow/pilot jet installed in them and that you may run into an aftermarket carb coming with a 21 series.
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on Jun 5, 2014 3:42:44 GMT -6
Anyone???
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 29, 2014 4:38:22 GMT -6
So besides the obvious what is the difference between these two jets. They are both marked size 38 they both were stock jets that came in 2 different carbs for a Jonway 54B 250cc Honda Clone. The threads are the same and the side with the orifices are the same length. The only thing that is different is how low they sit in the bowl. Just curious if any one else has run into this purchasing jets or carbs??? Attachments:
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 20, 2014 3:34:39 GMT -6
Really want to thank this thread for helping me fix my bike. As with rsw1158 replacing the carb was the fix. Sense we have a similar set up it made it easier for me to dial my bike in. I think my biggest hang up was understanding just what the bike was telling me. I was confusing a stumble and recover condition with what I guess to be a lean miss fire. After replacing the carb and doing a test run with a 115 main and a 38 pilot jet and the needle in the highest position the bike at around 3500 to 4000 would lose power and stumble but then would recover and move up into the 5500 RPM and would be fine (similar to my issue before replacing the carb). So I dropped to a 110 jet and the bike would barely run up my driveway?  ? SO if leaning makes it worse??? I jumped to a 117.5 jet and the power loss and stumble reduced so I went to a 120 jet and the bike ran up to 5000 rpm's with no issues, did a few straight away runs up and down the block a few times to include a few hard stops and rabbit starts and the bike seems brand new again. Thanks for your help guys. SUMMER RIDING IS HERE!!! |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 20, 2014 3:16:47 GMT -6
Thanks to another poster that was having the same issue as me with a similar set up it turns out replacing the carb was the fix. I rebuilt my original last year while the bike was having other issues but the way it was acting this go around was really throwing me.
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 16, 2014 9:15:06 GMT -6
I stopped at a Roketa dealer on my way to the lake yesterday. I just dropped in at chance to see what he had. He pulled this carb out of the loft and I inspected it noticing it had Japan casted on the side of the carb. I heard those are the good carbs so I went for it. He said his cost on that carb was 125.00. He sold it to me for 157.00. I was desperate so I bought it. It turned out to be the right choice. Do you have any mods are yours? I had to drop the air box because everything related to it broke so I'm running a 2 stage Uni filter. |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 14, 2014 3:22:55 GMT -6
I went out and bought a new carb today. It looks a lot like my oem carb except it sais Japan on the side. I opened it up and checked the jets. It had a 108 main and a 37 pilot. I changed them to a 125 main and a 38 pilot. I also checked the needle valve. Mine on the oem carb was not adjustable. This new one is. It has 4 slots for the clip. It was set on the lowest slot. I changed it to the second to the top slot. I installed the carb and started it up. First thing I noticed is that the enricher worked like it is supposed to. Before, even after trying a new enricher, it would start up slow idle and idle faster as it warmed up. That would be wrong. Next, after it warmed up, I tried to adjust the mix screw. It also acted like it was supposed to. Before, my carb was unresponsive unless I screwed it out a bunch. I made all my adjustments and took it for a ride. It is stupid windy today. Earlier today when I was working on it with the old carb, I could only go 60mph and it was bucking and surging and would smooth out after I backed off the throttle. Now, it goes 70mph against the wind and no bucking or surging. The old carb was the problem. If anyone that has this same scooter and having these problems, get rid of that junk carb. Find a quality carb and enjoy the ride. I hope this post will save a lot of headaches for someone else. Where did you pick up the new Carb? As we all know not all internet parts are the same or of any sort of quality. |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 13, 2014 10:24:47 GMT -6
Well, funny you should ask. I'm having issues again. It was running good for a few days, and now it is back to surging again in the mid range. Again, it is loosing power under load ( heavy head winds ) and bogging down. If I back off the throttle, it will smooth back out. Acting like it is too lean. Eventually I will get to the bottom of this problem. Well Damn, Same issue under load going up a hill or if I try to rabbit start off the line but it has to be hot outside (above 80°) if I'm at WOT though she runs like a top. |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 12, 2014 9:24:53 GMT -6
I got it all back together and didn't leave anything out of the carb. I did notice that there was rubber residue in the air mix screw but I don't see where it was blocking anything. So I started it up and let it get warm and started to adjust the carb. Again, I could close the screw all the way and wait and nothing happens. Idles perfect. I backed it out 1 3/4 turns and waited and nothing changed. I ran the rpms up and it surges a little between 4500 and 5500 rpm. So I started backing the screw out more and after about 3 turns it started to slow down. So, I turned it back in a 1/4 turn at a time until I achieved top rpm at idle and was running smooth. Ran the rpms up and no longer have the little surge between 4500 and 5500. I took it for a test drive and it runs out perfect for now. I'm going to drive it like this for a while and see how it does. Still don't seem right about the mix screw. How is all this working for you right now? What jets are you using. I am having similar issues with my bike but my issues is in the 3500 to 4000 range. |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 12, 2014 8:44:35 GMT -6
Sorry my bad thought it was the linhai. First of all the things you did as far as electric fuel pump install and removing the emissions system was all a waste of time unless there was vacuum leaks. Proven fact the engines run no better with the systems disconnected. A good vacuum fuel pump works just as good as a electric one if all lines are good and not leaking. Now since you mentioned you have added a filter from winter time to summer time riding conditions/weather are a totally different ball game, cold air runs better than hot/humid air. Now you've got to fine tune the air/fuel ratio to work correctly. I'll let Alley take over form here, he's the carb man. I don't see any mention of cleaning the carb especially the high speed jet orfice? JR Yeah I wish I didn't have to go the route of gutting the system out but it was spend $200 replacing all the broken, busted, cracked parts or dump it and spend $20 on a Uni and some new lines. But that was last year and 1000 miles ago. Anywhooo, The carb only take about 5 minutes to pull out now I didn't do a complete tear down cleaning but I did pull it and spray it down while doing the re jet. I'm sure if anyone out there has done this to there 54b's they might be able to give me a starting point on the jetting. This thing is a little more fickle then my 150cc was. |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 12, 2014 3:57:16 GMT -6
Vacuum leak and/or valves need adjusting. The linhai does weird things when especially the exhaust valve is too tight. JR Thanks for the reply, here are a few more things I have done. I did the valves as my first step, please note this is a 172mm Honda Clone, Also I have removed almost all vacuum from the system now so I am down to just one line for the carb. Last year I installed a UNI Dual Layer foam filter after my air box and everything related to that cracked and fell apart. I have dropped all emission equipment from the bike freeing about 10lbs off the thing. I was averaging around 65 to 70 mpg during the winter but now that warm spring is here I am garaged until I get this figured out. In my process to cure this current issue, I have gotten rid of the vacuum pump and I am now using an electric pump for fuel. At first I thought it was fuel starvation by the sound but its so hard to diagnose sounds through a helmet. I am honestly struggling with the is this a lean condition or a rich condition, A plug check shows that after 1000miles in the bike my plug looks the same as it did out of the box? ?? |
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 9, 2014 3:36:41 GMT -6
Well I upped the main jet from 115 to a 117.5 and my pilot jet from a 38 to a 40. I still have the issue but it occurs less frequently. So I went to a 120 jet and it just didn't run right. Back to the 117.5 jet and started moving the needle from its upper most setting with a shim down to the middle.
Still has the issue but not as bad. If anyone has any incite I would appreciate it. I would hate to be just bandaging this issue instead of doing it the right way.
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on May 5, 2014 13:04:11 GMT -6
Looking to the brain trust on this one. All winter long here in the south the bike ran with little to no issue. The last couple of days it has reach passed 80 degrees outside and the bike is giving me issues. This morning it was a cool 50 and I made the 7 mile trek to work with no issues. Today on the way home around the 5 mile mark the bike began to stud-er. Mostly after coming off the throttle then coming back on while traveling around 35mph. I was able to reproduce the issue while on that stand and made a video.
In the video I gave it about 1/4 to half 1/2 throttle and kept it there throughout the whole video. It would rise to 4000rpm on then down to 3000 and back up all on its own in the video while keeping my hand still on the throttle.
Any thoughts on what is making it bog / studder like this.
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on Oct 1, 2013 16:16:23 GMT -6
for my 2009 jonway54b with the honda clone its a 41mm
|
|
Sophomore
Currently Offline
Posts: 68
A+'s: 0
Joined: Apr 15, 2012 8:56:54 GMT -6
|
Post by Saber on Oct 1, 2013 16:04:07 GMT -6
okay made huge head way today, having two kids really limits when you can dedicate to working on and troubleshooting an engine,
Anyway, verified the slow jet was stock with a #35, removed and verified fuel/air screw was in good condition. Reinstalled and set it at 2 turns out. What got me running here was an oldie but goodie idea. I had to double shim with two small washers the needle. Most of my problems came from the mid range anyway. Once I did that she really opened up with no spits or studders. I was able to get up to 45mph in my neighborhood and maintain without issue. Tomorrow the skin goes back on and I will do a real world road test to see how she handles at true speeds.
I still have one question out there. Has anyone ever put a uni filter on there yy250 54B? What main jet did they end up going with. I have a 102,105,110,115,120,125,127and130 on hand. Currently i'm running with the 115.
|
|
