Also you can cut small amount of cable housing to can fit keihin and get correct free play. He is doing this because he removered stock mikuni carb and installed keihin, without doing this mod the free play will be to small and causing problems... Solutions to get correct play are getting longer cable,new throttle cam body (from older models) or cut cable housing or doing same mod from video,
With the top of the loop of the bowl drain hose higher than the internal bowl overflow tube, won't fuel run through the carburetor towards the intake before it can escape via the drain tube?
Please pause the video at 4:32. The fuel overflow hose (connects to bottom of the carb bowl) is routed down so that fuel can flow out. It does have a small loop to help prevent spillage while riding over rough ground. You can include choose not to use the loop if you prefer. Yes, the fuel overflow tube must not be routed up higher than the carb intake level, or fuel may flow into the crankcase if the fuel valve is stuck open.
The free play is when the throttle is fully closed. When you have the throttle open there is no play. I just want to make the amount of free play be in the middle of the specified value.
I’ve got this same carb on my husqvarna tx125 2017 and it doesn’t seem to want to Rev full throttle it bogs until you clear it and it eventually Revs out
by routing the overflow that way wouldn't you effectively be changing the overflow level of the carb if the top of the loop is higher than the overflow port on carb?
Fuel can still escape when the bike is tipped over on it’s side, preventing flooding of the cases. The big difference is that fuel can’t easily slosh out during normal riding, thus improving fuel economy. It’s seems to be a common and popular mod for Keihin and Mikuni carbs, with no downside as far as I can see.
Thanks for explaining that. I noticed JD also recomended doing that in their jet kit instructions. I took your advice on the cost effective fix for the Mikuni with that kit, setting float height, and the s1 needle. Running much much better!!! :)
There are several ways to increase the free play. I choose to mill the carb cap. Other methods include reducing the thickness of the nut on the throttle cable adjuster at the throttle tube, or using a longer cable (with same length cable sheath).
I installed a Motion Pro T3 Cable for a 2016 KTM 300 XC. I have a (2017 300 XC - not sure if XC and XCW are different but I assume not). It’s Only available in the longer (in front of bars) length.
Thank's so much, in the middle of setting my float thought i check you out, glad i did. It's easier to work with a point of reference, smart on your part ( FACTORY should have done it). If I'm working on my Husky TE300 i will check out Tokyo Offroad for info. Dirt Bike Information for Dummy's (me-joke). Happy trails. kILLER Videos
raising the upper vent tubes is pointless with our raising the other 2 all 4 tubes feed the same 2 orifices into the float bowl .. i have the same carb and have all my vent lines routed upward to a large filter .. the filter is way oversized so it doesn't restrict flow but prevents dust from being pulled in in dusty environments i often ride .. it is also possible to suck dirt into the overflow tube . the loop ive also done helps prevent sucking in dust because the fuel that gets trapped inside acts like a drain trap on a sink . so good on that one
On my sons account, do you no spec for mikuni float height? is it same a Keihin? cannot find it anywhere! been on the ktm,s for years and now have 18 xc 250 which to be fair bar a bit of fuel leaking out runs great with Mikuni after a bit of jet and needle swapping, biggest improvement I think was popping the S1 needle jet from my sons 18 250 sx in, why they don,t fit them from stock is baffling.
AXO Hey Tokyo did you abandon the Mikuni and install this keihin on your 300 ? If so does the stock throttle cable work on the keihin ? Im thinking of giving up on the mikuni. What elev and temps do you ride at and what jetting did you end up with?
My bike is a 250, but yes, I’m running the Keihin with the stock throttle cable. The mod I made to the carb top plate (milled off 2mm) give plenty of throttle free play (spec is 3~5mm) with the stock cable. Elevation is typically 500~1,500m, Temp is 0~30degC. I’m still using the baseline JD settings (pilot=42; air screw~1.5; needle=red 3rd clip; main=172) and the bike is running great (last weekend was about 500~1,000m, 2~10degC)
The good day I just talked to my mechanic about the gasoline tube. He said that this tube serves to ensure that after bike falling a lot of gasoline did not fall into the cylinder. And the motorcycle will not start. Do you have any problems with starting the motorcycle after the fall? Sorry for my English )))
No, the bike starts very easily after falls. I have heard that with the overflow loop some overflow fuel will sit in the loop and can get sucked back into the bowl, causing the fuel level to rise for a short amount of time. However, I haven’t really noticed a detrimental effect on performance.
Thanks for the answer, I will try. Usually we have very long trips and sometimes we do not have enough gas. I hope this loop will reduce the consumption of gasoline. If interested - look at my video - it's Crimea.
Tokyo offroad.... Excellent videos, best on TH-cam! Thanks for uploading them. Would you happen to know if a throttle cable for a '16 150 SX would fit correctly on a '17 300 XC with a PWK38 AG shorty? I don't have access to a milling machine and also don't want to waste money buying the wrong cable. Thx in advance
I’m not sure what cable will fit as I just used the stock cable. I used the milling machine as I have one, but you could easily file down the carb cover as it’s made of Aluminium and use the stock cable.
I've been thinking about your suggestion to reduce the thickness of the throttle cable adjustment nut. The big problem with that is that the nut can not easily be removed from the cable. You'd need to remove the cable nipple to take the nut off. Then with each new cable you buy you'd need to do the same thing. As such the mod I did (mill the carb top cover) is much easier it you want to use the stock cable.
Researched online. The setting I decided on is 7mm when the carb is at 60degrees. You can see me checking the float height in this video: th-cam.com/video/96949V9hdVc/w-d-xo.htmlm9s
OK thanks. I couldn't find any thing from the manufacturer but did find 3 different ways online to check the level including yours. However they all gave me a different result lol but sort of close I guess. I had a factory green marker line on my carb about where the float should be, I noticed yours did not. I assume they give them a quick check on the assembly line so will assume at this point that it is with in some parameters of sorts (hopefully not a Friday arvo parameter). I will install the carb as is and take it from there. Cheers!
nuked nuked - Mine has all the factory calibration and check marks on too. The method I used (7mm when the carb is at 60degree angle) results in the float being level at that angle. As noted in the video I didn’t need to adjust the float height from the factory (or maybe JD) setting. It’s always good to check though, particularly if you notice you’re getting poor fuel economy. I think you’ll like the Keihin :-)
the height can affect the overall jetting by a small amount ..and if running different fuel types like alchy or race fuels they have different gravity .. this means they have different buoyancy affect on the float and may require a float adjustment . if your carb has a drain screw u can use a clear over flow tube raised above the bowl and open the drain and see the exact fuel height.
Herman Wallin - A little slack helps ensure that the slide can fully close. The slack also makes the carb insensitive to small hand movements when the throttle is closed. Once you start to open the throttle there will be no perceptible difference between no slack and having slack.
I got the bike running pretty well with the Mikuni and a JD Jetting kit. However, the bottom end was never that great and it was always sensitive to elevation and temp changes. The Keihin works so much better, especially with a STIC metering block...
Suggest you consider installing the new STIC metering block; 10 minutes away from incredible performance to go with your modification; call Harris performance.
George Boswell - I’m really happy with how the Keihin runs with the JD Jetting kit. It runs clean and crisp at all throttle openings so I’m not seeking to make any changes.
I hate play in the throttle tube, why would anyone want that? I set my throttle up so that it has the minimum amount of play that I can get away with so that the revs don't rise when you turn the steering from lock to lock.
Thank you !! finally , what I was looking for !!
Very helpful video ! I did a deep water crossing on the weekend and it quit on me half way through.Going to route the vent tubes your way .
Also you can cut small amount of cable housing to can fit keihin and get correct free play. He is doing this because he removered stock mikuni carb and installed keihin, without doing this mod the free play will be to small and causing problems... Solutions to get correct play are getting longer cable,new throttle cam body (from older models) or cut cable housing or doing same mod from video,
Has your TPI still a throttle cable or is it ride by wire ?
With the top of the loop of the bowl drain hose higher than the internal bowl overflow tube, won't fuel run through the carburetor towards the intake before it can escape via the drain tube?
Please pause the video at 4:32. The fuel overflow hose (connects to bottom of the carb bowl) is routed down so that fuel can flow out. It does have a small loop to help prevent spillage while riding over rough ground. You can include choose not to use the loop if you prefer. Yes, the fuel overflow tube must not be routed up higher than the carb intake level, or fuel may flow into the crankcase if the fuel valve is stuck open.
great job,great video, but I didn't understand why you must have more free play in throttle.
The free play is when the throttle is fully closed. When you have the throttle open there is no play. I just want to make the amount of free play be in the middle of the specified value.
you always make good videos. right to the point thank you.
I’ve got this same carb on my husqvarna tx125 2017 and it doesn’t seem to want to Rev full throttle it bogs until you clear it and it eventually Revs out
by routing the overflow that way wouldn't you effectively be changing the overflow level of the carb if the top of the loop is higher than the overflow port on carb?
Fuel can still escape when the bike is tipped over on it’s side, preventing flooding of the cases. The big difference is that fuel can’t easily slosh out during normal riding, thus improving fuel economy. It’s seems to be a common and popular mod for Keihin and Mikuni carbs, with no downside as far as I can see.
Thanks for explaining that. I noticed JD also recomended doing that in their jet kit instructions. I took your advice on the cost effective fix for the Mikuni with that kit, setting float height, and the s1 needle. Running much much better!!! :)
Great video, do you have a link for the vents? Thx
The KTM part number is 7723199700004
great video!
There is no way to earn this throttle's free play without girding off some metal? maybe longer cable?
There are several ways to increase the free play. I choose to mill the carb cap. Other methods include reducing the thickness of the nut on the throttle cable adjuster at the throttle tube, or using a longer cable (with same length cable sheath).
I installed a Motion Pro T3 Cable for a 2016 KTM 300 XC. I have a (2017 300 XC - not sure if XC and XCW are different but I assume not). It’s Only available in the longer (in front of bars) length.
Thank's so much, in the middle of setting my float thought i check you out, glad i did. It's easier to work with a point of reference, smart on your part ( FACTORY should have done it). If I'm working on my Husky TE300 i will check out Tokyo Offroad for info. Dirt Bike Information for Dummy's (me-joke). Happy trails. kILLER Videos
what jets did you install ?
I am jealous of your workshop! I am hoping a 12" Bastard / Warding file will suffice.
Do you know what is internal diameter of that vent hoses?Is it the same size in mikuni carb?
raising the upper vent tubes is pointless with our raising the other 2 all 4 tubes feed the same 2 orifices into the float bowl .. i have the same carb and have all my vent lines routed upward to a large filter .. the filter is way oversized so it doesn't restrict flow but prevents dust from being pulled in in dusty environments i often ride .. it is also possible to suck dirt into the overflow tube . the loop ive also done helps prevent sucking in dust because the fuel that gets trapped inside acts like a drain trap on a sink . so good on that one
What number slide do you have in that carburettor? I have an '18 250 EXC and I am going to try a PWK38 from a 125SX that has a "7" slide.
Mine has a 6.5 slide in it.
On my sons account, do you no spec for mikuni float height? is it same a Keihin? cannot find it anywhere! been on the ktm,s for years and now have 18 xc 250 which to be fair bar a bit of fuel leaking out runs great with Mikuni after a bit of jet and needle swapping, biggest improvement I think was popping the S1 needle jet from my sons 18 250 sx in, why they don,t fit them from stock is baffling.
The information I have states that the Mikuni float height spec is 8.7 +/-1.0mm.
@@TokyoOffroad Thank you, please disregard message on your website, regards jason
@@peb7507 - No problem...
AXO Hey Tokyo did you abandon the Mikuni and install this keihin on your 300 ? If so does the stock throttle cable
work on the keihin ? Im thinking of giving up on the mikuni. What elev and temps do you ride at and what jetting did you end up with?
My bike is a 250, but yes, I’m running the Keihin with the stock throttle cable. The mod I made to the carb top plate (milled off 2mm) give plenty of throttle free play (spec is 3~5mm) with the stock cable. Elevation is typically 500~1,500m, Temp is 0~30degC. I’m still using the baseline JD settings (pilot=42; air screw~1.5; needle=red 3rd clip; main=172) and the bike is running great (last weekend was about 500~1,000m, 2~10degC)
Hi there good videos 👍🏻
The good day
I just talked to my mechanic about the gasoline tube. He said that this tube serves to ensure that after bike falling a lot of gasoline did not fall into the cylinder. And the motorcycle will not start.
Do you have any problems with starting the motorcycle after the fall?
Sorry for my English )))
No, the bike starts very easily after falls. I have heard that with the overflow loop some overflow fuel will sit in the loop and can get sucked back into the bowl, causing the fuel level to rise for a short amount of time. However, I haven’t really noticed a detrimental effect on performance.
Thanks for the answer, I will try.
Usually we have very long trips and sometimes we do not have enough gas.
I hope this loop will reduce the consumption of gasoline.
If interested - look at my video - it's Crimea.
the over flow will also prevent fuel from flooding the engine if the float hangs up or piece of debris jams the float needle .
Tokyo offroad.... Excellent videos, best on TH-cam! Thanks for uploading them.
Would you happen to know if a throttle cable for a '16 150 SX would fit correctly on a '17 300 XC with a PWK38 AG shorty? I don't have access to a milling machine and also don't want to waste money buying the wrong cable. Thx in advance
I’m not sure what cable will fit as I just used the stock cable. I used the milling machine as I have one, but you could easily file down the carb cover as it’s made of Aluminium and use the stock cable.
Good video !But if it was mine I would take 2 millimeters from that nut in a lathe !
Yes, that's another way of doing it.
I've been thinking about your suggestion to reduce the thickness of the throttle cable adjustment nut. The big problem with that is that the nut can not easily be removed from the cable. You'd need to remove the cable nipple to take the nut off. Then with each new cable you buy you'd need to do the same thing. As such the mod I did (mill the carb top cover) is much easier it you want to use the stock cable.
I'm planning to set my vent tubes up this way. Are you still running the same set up?
Shawn Preston - Yes, I still have the vents the same way. No issues at all.
Hi! Just setting my Keihin up now. Where did you get the info regarding float level height? Cheers your channel is so helpful to me!
Researched online. The setting I decided on is 7mm when the carb is at 60degrees. You can see me checking the float height in this video: th-cam.com/video/96949V9hdVc/w-d-xo.htmlm9s
OK thanks. I couldn't find any thing from the manufacturer but did find 3 different ways online to check the level including yours. However they all gave me a different result lol but sort of close I guess. I had a factory green marker line on my carb about where the float should be, I noticed yours did not. I assume they give them a quick check on the assembly line so will assume at this point that it is with in some parameters of sorts (hopefully not a Friday arvo parameter). I will install the carb as is and take it from there. Cheers!
nuked nuked - Mine has all the factory calibration and check marks on too. The method I used (7mm when the carb is at 60degree angle) results in the float being level at that angle. As noted in the video I didn’t need to adjust the float height from the factory (or maybe JD) setting. It’s always good to check though, particularly if you notice you’re getting poor fuel economy. I think you’ll like the Keihin :-)
the height can affect the overall jetting by a small amount ..and if running different fuel types like alchy or race fuels they have different gravity .. this means they have different buoyancy affect on the float and may require a float adjustment . if your carb has a drain screw u can use a clear over flow tube raised above the bowl and open the drain and see the exact fuel height.
I don't own a mill. do you think I can just use a metal file?
Yes, you should be able to file it down easily. Be sure to carefully clean out any debris after filing it down.
why would you want slack in the cable?
Herman Wallin - A little slack helps ensure that the slide can fully close. The slack also makes the carb insensitive to small hand movements when the throttle is closed. Once you start to open the throttle there will be no perceptible difference between no slack and having slack.
Good video, and what happeed with the mikuni carburator?😄 do not work well 😂 , i love keihin carburetor ❤️
I got the bike running pretty well with the Mikuni and a JD Jetting kit. However, the bottom end was never that great and it was always sensitive to elevation and temp changes. The Keihin works so much better, especially with a STIC metering block...
Where do you order all your ktm parts from?
HybridEdits - I order my KTM OEM parts from my local KTM dealer in Tokyo, Japan. For non-OEM parts I order from online shops in the US and Europe.
what are symptoms of a bad float height?
Punkman98 if the fuel level is too high you’ll get poor fuel economy, if the fuel level is too low you could starve the engine of fuel during WOT.
Suggest you consider installing the new STIC metering block; 10 minutes away from incredible performance to go with your modification; call Harris performance.
George Boswell - I’m really happy with how the Keihin runs with the JD Jetting kit. It runs clean and crisp at all throttle openings so I’m not seeking to make any changes.
I hate play in the throttle tube, why would anyone want that? I set my throttle up so that it has the minimum amount of play that I can get away with so that the revs don't rise when you turn the steering from lock to lock.