Need help setting nibbi pe28 carb for SRR RAZKULL 125CC

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Chad03

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Hello there I have a Vader 125cc and I have a 141 big bore kit on it with aftermarket exhaust and performance cam. I found out with mine that I had a genuine mikuni 26mm and it was a little to big for my application I ended up going to a genuine mikuni VM24-512 and it worked out much better was actually able to tune the carb and get the bike to run amazing.
 

krl062190

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hey there Chad appreciate you responding back I was beginning to think that no one was going to respond yeah here lately I have been been able to have it running pretty rideable I should say I'm able to write it to and from work right now with no issues except for the fact that if it does rain I'm pretty much dead in the water because of the filter situation ever take ever since I took the breather box off riding in the rain is not happening but as far as my nibbi pe28 it's actually you working out pretty good now I finally was able to figure out the ratio of the fuel and air ratio a little bit to the point to where it's it's finally idling right but I still have some bogging down from shifting between 2 and 3rd gear and once I get up to 4th gear and around 5253 miles an hour it wants to bog down to almost completely to when it stalls out so did I was then I started playing with the Jets to tune the carb and this is actually my very first time actually ever you know even messing with a jet carb or doing my own type of service to tee it or anything like that so I might I'm learning at the same time so any help or advice that you had passed would be highly appreciated right now I am running it with a 40 pilot jet and a 115 name jet at first I started to work with a lower Jax started out with I 100 Main Jet and was going to work my way up because it came stock with the 115 Main Jet in it and I wanted to let you know I'm my goal is to get the bike like around to run anywhere from 75 to 80 miles an hour so I'm able to be on the highway and not have to worry about you know other people being all my ass and having to go around me or stuff like that I want to be able to get up out there way if I need to quick enough and be comfortable on the freeway but back to the Jets so it came stock with a 115 I went down a couple increments and then nothing there went down a little more no help so I went all the way down to haha the 100 size Main Jet and then I said alright well I'm going back up so I ended up working my way back up to the 115 and right now it's running pretty pretty decent other than the fact that it it idles a little high but I believe that's what it's going to happen because of the fact that I did buy a bigger carburetor but I'm sure that it will Ryan it's best once I figure out this whole carburetor tuning thing I really didn't know what size Jets to start out at and work towards or anything like that so I'm basically just guessing it and listening to the motor and doing it that way but my bike is completely stock besides the carborator the air intake and filter and exhaust and now I just and now I just got my 17 tooth front Sprocket in the mail today
 

Chad03

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hey there Chad appreciate you responding back I was beginning to think that no one was going to respond yeah here lately I have been been able to have it running pretty rideable I should say I'm able to write it to and from work right now with no issues except for the fact that if it does rain I'm pretty much dead in the water because of the filter situation ever take ever since I took the breather box off riding in the rain is not happening but as far as my nibbi pe28 it's actually you working out pretty good now I finally was able to figure out the ratio of the fuel and air ratio a little bit to the point to where it's it's finally idling right but I still have some bogging down from shifting between 2 and 3rd gear and once I get up to 4th gear and around 5253 miles an hour it wants to bog down to almost completely to when it stalls out so did I was then I started playing with the Jets to tune the carb and this is actually my very first time actually ever you know even messing with a jet carb or doing my own type of service to tee it or anything like that so I might I'm learning at the same time so any help or advice that you had passed would be highly appreciated right now I am running it with a 40 pilot jet and a 115 name jet at first I started to work with a lower Jax started out with I 100 Main Jet and was going to work my way up because it came stock with the 115 Main Jet in it and I wanted to let you know I'm my goal is to get the bike like around to run anywhere from 75 to 80 miles an hour so I'm able to be on the highway and not have to worry about you know other people being all my ass and having to go around me or stuff like that I want to be able to get up out there way if I need to quick enough and be comfortable on the freeway but back to the Jets so it came stock with a 115 I went down a couple increments and then nothing there went down a little more no help so I went all the way down to haha the 100 size Main Jet and then I said alright well I'm going back up so I ended up working my way back up to the 115 and right now it's running pretty pretty decent other than the fact that it it idles a little high but I believe that's what it's going to happen because of the fact that I did buy a bigger carburetor but I'm sure that it will Ryan it's best once I figure out this whole carburetor tuning thing I really didn't know what size Jets to start out at and work towards or anything like that so I'm basically just guessing it and listening to the motor and doing it that way but my bike is completely stock besides the carborator the air intake and filter and exhaust and now I just and now I just got my 17 tooth front Sprocket in the mail today
You May get it to run pretty decent but you will prob never get it to run perfect to be honest. Just my opinion when I say this bec this happened to me. When I tried the mikuni 26-606 carb on mine with all the mods I had done to it it acted just like yours did. I could either get it to run ok down low or ok up high never even. I tried changing out the jets in it a lot and still really couldn’t get it. I was doing some digging online and ran across other people saying the same thing and same issues. And remind you mike has a 141 big bore kit on it with custom exhaust performance cam also. I bought a mikuni VM24-512 a genuine one and man I love it it has power through every gear and it’ll straight get up and fly also. I also have a 17T front sprocket and 31T rear sprocket to try to help with the speed and cruising so the rps aren’t as high.
 

Chad03

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You May get it to run pretty decent but you will prob never get it to run perfect to be honest. Just my opinion when I say this bec this happened to me. When I tried the mikuni 26-606 carb on mine with all the mods I had done to it it acted just like yours did. I could either get it to run ok down low or ok up high never even. I tried changing out the jets in it a lot and still really couldn’t get it. I was doing some digging online and ran across other people saying the same thing and same issues. And remind you mike has a 141 big bore kit on it with custom exhaust performance cam also. I bought a mikuni VM24-512 a genuine one and man I love it it has power through every gear and it’ll straight get up and fly also. I also have a 17T front sprocket and 31T rear sprocket to try to help with the speed and cruising so the rps aren’t as high.
And how you was saying it idles high is your throttle cable to tight or pinched up? If there isn’t enough slack in it it’ll do that
 

krl062190

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Hey there hey there Chad yeah right now man in the bikes running pretty decent right now my RPMs are now are pretty low with that do 17 front sprocket and I have the 34 still on there I think is what it is right now I'm running a 120 Main Jet and a 42 pilot but it's still not running the way I wanted the wrong but it is running decent and my throttle cable is the nibbi high performance throttle cable and I I think it has a default and it because for some odd reason it keeps getting stuck and. Revs it up to red lineing it. but the throttle cable is extremely long like I've had to reroute it in and around my bike a whole time then to the carburetor so I think that also could be the reason why so I just got my new throttle housing and tube and swaddle Cable in today in the mail tonight I'm working on the bike to put in that new throttle cable and throttle housing and tube this is my 3rd one so hopefully this will be the the last one but Chad what's the where do you stay at are you down south or you up north or you know what's your weather like riding your bike and quick question is yours carburetor and filter does it stick out does your filter stick out towards your forks or do you still able to have it mounted words up underneath the gas tank and you know not out in the open?
 

Chad03

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Hey there hey there Chad yeah right now man in the bikes running pretty decent right now my RPMs are now are pretty low with that do 17 front sprocket and I have the 34 still on there I think is what it is right now I'm running a 120 Main Jet and a 42 pilot but it's still not running the way I wanted the wrong but it is running decent and my throttle cable is the nibbi high performance throttle cable and I I think it has a default and it because for some odd reason it keeps getting stuck and. Revs it up to red lineing it. but the throttle cable is extremely long like I've had to reroute it in and around my bike a whole time then to the carburetor so I think that also could be the reason why so I just got my new throttle housing and tube and swaddle Cable in today in the mail tonight I'm working on the bike to put in that new throttle cable and throttle housing and tube this is my 3rd one so hopefully this will be the the last one but Chad what's the where do you stay at are you down south or you up north or you know what's your weather like riding your bike and quick question is yours carburetor and filter does it stick out does your filter stick out towards your forks or do you still able to have it mounted words up underneath the gas tank and you know not out in the open?
You May just have to keep on messing with it. Just remember bigger isn’t always better when it comes to stuff like this lol. But what I did I bought this cable clamp that goes over like your clutch cable or brake cable and you screw it on and spray line through it so the cable isn’t stiff in the housing and lets it slide better so it doesn’t get hung up. Idk if you watch any YouTube but there is a guy on there called throttlefamily and he done a comparison with the nibby 26mm carb vs the fake mikuni vm22 26mm carb. He had all kinds of trouble trying to get the nibby carb setup also and he eventually went back to the Chinese vm22 26mm carb. You will have to watch it. But I live in WV. During the summer it’s high 90s and sunny but winter it snows so can’t really ride then. But the way I have mine setup is the carb and filter faces the forks. I’ll upload a few pics to show you my setup.
 

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krl062190

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You May just have to keep on messing with it. Just remember bigger isn’t always better when it comes to stuff like this lol. But what I did I bought this cable clamp that goes over like your clutch cable or brake cable and you screw it on and spray line through it so the cable isn’t stiff in the housing and lets it slide better so it doesn’t get hung up. Idk if you watch any YouTube but there is a guy on there called throttlefamily and he done a comparison with the nibby 26mm carb vs the fake mikuni vm22 26mm carb. He had all kinds of trouble trying to get the nibby carb setup also and he eventually went back to the Chinese vm22 26mm carb. You will have to watch it. But I live in WV. During the summer it’s high 90s and sunny but winter it snows so can’t really ride then. But the way I have mine setup is the carb and filter faces the forks. I’ll upload a few pics to show you my setup.

We will check out the video add get it I have my set up the same way I've been trying to figure out a way to basically turn it around so it stuck back underneath only because of rain issue with living down in Florida I get a lot of rain bad rain hits. Filter is gone I'm sitting dead in the water you know he's just got to wait till it to dry out or or what so I'm trying to figure out something or some way to refrain from it dying in the rain yes I happened to be writing and it starts raining but yeah you are right about all bigger isn't always better I have learned that the hard way you know cuz you know I'm still kind of new I'm trying to figure out should the main jet be bigger or smaller than the pilot jet or or do I just have to keep pulling the plug and see and if I'm running too rich or too lean I guess that's the only way
 

krl062190

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Will definitely watch that video do you know what the part is called or where to get the part at where the sprocket attaches to the back wheel I guess it's called a sprocket driving wheel hub or something like that if you have any idea what it is called or where to get it I'm lost at that because I'm needing to get a new one because when I went to put a bigger back sprocket on I kind of messed messed up the Hub and it again it's where the sprocket bolts onto the back wheel that piece behind the sprocket
 

Chad03

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To be honest the best way would be to keep on doing plug checks. I know you said you had an after market exhaust on there but what’s the diameter of your exhaust pipe? With a carb that big your gonna want a pretty good exhaust on there since that big of a carb is going to be moving a lot of air. That can create a hold back also. Just out of curiosity what clip position is your needle clip on? Like from the top counting down? But where I get all my parts from is a place called TBolt.com. They have all kinds of pit bike parts on there and you May even find the hub on there you need to fix your sprocket. They have all kinds of stuff on there and they also have different kinds of intake pipes that face out like we have and ones that face inwards like stock use to be. Like for my set up I know it’s going to be way different than yours but mine has a 17.5 pilot a 130 main I can prob do a 140 and my needle clip position is in the middle slot.
 

krl062190

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Snapping the bowl off putting on the new rear sprocket and so I had to drill out that Bolt and put in a different bolts and a nut at the bottom of it will end the just of all of that I ended up wildin it out a little too much and for the small hairline crack down me the part where the Bolt hole is and I don't know what the dimensions are for the back tire other than the fact that it's a 12 170 ar12 I don't know what the sprocket dimensions are without having to take it off pull it all apart and then measure it and then put it back together but I do know but I need to get it fixed before it cracks all the way while I'm riding I'll post some pictures when I get off of work today
 
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