Need advice- 2016 KTM 300XC intake/airbox mods

[chrispy1202]

Wondering what everyone is doing for their intake and filter set ups for their 2 smokers... Just trying to get my bike all ready to go with my "new to me", 2018 ARO 120 kit. I have a Timbersled intake from my last Kawi 450 snow bike, but it doesn't look like it will work without cutting the whole airbox apart, and even then maybe still won't work. I installed a Lectron carb and carb heater. The OD of the carb heater is 2.5". I am thinking about getting a silicone 45 degree tubing elbow and mounting a pod filter with the snow screen on it, and hopefully it will fit in the airbox... is this what most guys are running?? I removed the whole airbox, but because the battery mounts in it, i'd like to keep it if possible. Please snap a picture of what is working well for you if you can. I was hoping to not have to butcher the airbox if possible, but if that is what has to be done that's all good. Want to measure twice and cut once haha! Cheers!!

 

[HalfBrit]

I just put a prefilter in place of the filter. in deep pow you'll feel a loss in power when it fills up with snow. just pop the cover and scoop it out.

 

[chrispy1202]

I just put a prefilter in place of the filter. in deep pow you'll feel a loss in power when it fills up with snow. just pop the cover and scoop it out.

There isn't room to use the stock intake when the carb heater is in place... Looks like i have to remove the stock filter and try to use a silicone tubing 45 and a pod filter with a snow pre filter... anyone else have to do this??

 

[tribalbc]

There isn't room to use the stock intake when the carb heater is in place... Looks like i have to remove the stock filter and try to use a silicone tubing 45 and a pod filter with a snow pre filter... anyone else have to do this??

That's how I have my Kx500 set up.

 

[Answ3r]

Wondering what everyone is doing for their intake and filter set ups for their 2 smokers... Just trying to get my bike all ready to go with my "new to me", 2018 ARO 120 kit. I have a Timbersled intake from my last Kawi 450 snow bike, but it doesn't look like it will work without cutting the whole airbox apart, and even then maybe still won't work. I installed a Lectron carb and carb heater. The OD of the carb heater is 2.5". I am thinking about getting a silicone 45 degree tubing elbow and mounting a pod filter with the snow screen on it, and hopefully it will fit in the airbox... is this what most guys are running?? I removed the whole airbox, but because the battery mounts in it, i'd like to keep it if possible. Please snap a picture of what is working well for you if you can. I was hoping to not have to butcher the airbox if possible, but if that is what has to be done that's all good. Want to measure twice and cut once haha! Cheers!!

Make sure to get the shortest tubing possible, or get one that tapers to a MUCH bigger diameter or it will mess big time with the tuned intake tract length and kill a bunch of power.

Carbed 2t are WAY more sensible to that that F/I 4t.

 

[cct22]

Here’s my setup for my 2016 Te300. Will be my first year as a snowbike. Silicone Hose 2.5 to 3inch with a custom made pod filtrer.
Tested it yesterday and it look alright

 

[chrispy1202]

That's how I have my Kx500 set up.

View attachment 363860

that looks good, i will stick my airbox back on and do some measuring. Thank You!

 

[chrispy1202]

Here’s my setup for my 2016 Te300. Will be my first year as a snowbike. Silicone Hose 2.5 to 3inch with a custom made pod filtrer.
Tested it yesterday and it look alright

Sweet! I didn't want to have to leave the airbox off if possible. That looks like it will work well. I can't wait to get it all together and get out in the snow. Watching videos is making me a bit stir crazy. Thank you!

 

[chrispy1202]

Make sure to get the shortest tubing possible, or get one that tapers to a MUCH bigger diameter or it will mess big time with the tuned intake tract length and kill a bunch of power.

Carbed 2t are WAY more sensible to that that F/I 4t.

I will see if i can get a tapered piece for in between the carb heater and intake filter. Thank you!

 

[portgrinder]

In some conditions it’s nice to have the sides of your air box still there to shield the filter from the chain/exhaust. In warmer weather, these can cause the filter to get soaked.

short and tapered intakes are both a good idea. If you have a powerjet, you might need a couple inches of intake in front of the carb. I have seen super short intakes make the powerjet run erratically in some cases.

If you have good heat, don’t get too worried about the filter as long as it’s dry. You can have a couple pinholes etc in it with no issues. Don’t need to double filter etc. I run a little deicer in my fuel as well.

 

[tribalbc]

In some conditions it’s nice to have the sides of your air box still there to shield the filter from the chain/exhaust. In warmer weather, these can cause the filter to get soaked.

short and tapered intakes are both a good idea. If you have a powerjet, you might need a couple inches of intake in front of the carb. I have seen super short intakes make the powerjet run erratically in some cases.

If you have good heat, don’t get too worried about the filter as long as it’s dry. You can have a couple pinholes etc in it with no issues. Don’t need to double filter etc. I run a little deicer in my fuel as well.

I had a small hole in my filter before on a super deep cold dry day and my filter let in so much snow I washed all the oil off my piston on the kx5 and had a partial seizure.
I always double bag now with one stock two layer prefilter and just the outer layer of another one over top. Inspect often and I find I am lucky to get a season out of them before they lose their waterproofing.

 

[portgrinder]

That’s interesting. I ran about 6 barrels of fuel thru my k5 before I sold it. I was always fighting with filter issues until i had good heat to my carb and a little deicer in the fuel.

 

[portgrinder]

That’s interesting. I ran about 6 barrels of fuel thru my k5 before I sold it. I was always fighting with filter issues until i had good heat to my carb and a little deicer in the fuel.

One thing I also did was run a looser tolerance on my piston. Did that after I smeared a few.

 

[tribalbc]

One thing I also did was run a looser tolerance on my piston. Did that after I smeared a few.

Yeah I run a little looser tolerance on my piston as well.
As you say carb heat is crucial and I run a mix of avgas so I have deicer in there.
The biggest issue I found was positioning the filter where it wouldn't clog up on deep days. I have found the happy spot now. I had to use a little longer intake but any performance loss there is outweighed by keeping the filter snow free in my eyes.

 

[roxiedog13]

Avgas does not contain a deicing solution, it's just less prone to vapor lock in warmer conditions compared to auto fuel. Also realize untreated pure Avgas has a lot of lead in the mixture and it's not good for our engines as I understand. Blue Avgas is 100 octane, most premium autofuels are around 92%, so I doubt there is really any advantage. Well, I suppose if you are running a really high compression engine at the limits of performance there is the possibility of detonation, the higher octane low lead fuel will help . The lead will however foul plugs and build up on the rings and valves, so you gain a short term advantage over long term issues. I use both premium autofuel and avgas in my airplane, I have yet to notice any difference in performance. I run AVgas only as necessary to purposely get a film of lead on the valves as necessary for these engines.