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Looking to go down the route of sticking a PWK carb on my bike instead of the stock mikuni. Mikuni has had jarvis mods and runs well but has a few off days where it just feels lean and rich on the same day???
So Tokyo off road promote the 38mm eurotek promote the 36mm lots of mixed reviews
Has anybody tried both back to back
I do feel if the ktm engineers sent it out the factory with a 38mm Carb on it there was a reason over doing that rather than a 36mm???
 

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Tokyo may have stated that the 38 is the carb to go for but that might be if you use a STIC metering block, he is one of the people that tested the block. (as am I).

I've not watched all of his vids but bear the above in mind.
 

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Discussion Starter #4
Tokyo may have stated that the 38 is the carb to go for but that might be if you use a STIC metering block, he is one of the people that tested the block. (as am I).

I've not watched all of his vids but bear the above in mind.
How do you get on with the stic, this has grabbed dmy interest for sure
 

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How do you get on with the stic, this has grabbed dmy interest for sure
I don't want to turn this into a STIC thread, there are a couple of these on this forum already but put it this way, once its dialled in which easier to do now than it was to do a couple of years ago the STIC block is shockingly good, the low down 'snap' that my old 2013 has is great, it makes you look like a better rider than you really are. Having said that you need to keep your wits about you or could end up on your ass, you just have to 'calibrate' your throttle control the first few times that you ride a STIC equipped bike.

Check this out...

STIC Metering block, my thoughts on the device! | KTM Owners Forum (ktmforum.co.uk)
 

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Wow, we run a 39mm (modded to that size) PWK on our 19 race 125.
Good point, what size engine are we talking about here. I guess with a 125 there is no bottom end anyway so there is nothing to lose with a massive carb, the engine is just kept screaming from start to finish!
 
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Good point, what size engine are we talking about here. I guess with a 125 there is no bottom end anyway so there is nothing to lose with a massive carb, the engine is just kept screaming from start to finish!
125's don't have a throttle, just an on/off switch 😁
 
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Looking to go down the route of sticking a PWK carb on my bike instead of the stock mikuni. Mikuni has had jarvis mods and runs well but has a few off days where it just feels lean and rich on the same day???
So Tokyo off road promote the 38mm eurotek promote the 36mm lots of mixed reviews
Has anybody tried both back to back
I do feel if the ktm engineers sent it out the factory with a 38mm Carb on it there was a reason over doing that rather than a 36mm???

What are these so called Jarvis mods?
 

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What are these so called Jarvis mods?
Fiddling with a shite carb to try and improve how it works. Still not like we’ll set up Keihin.
 

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I’d do some digging in jetting threads from around 2015. That was the Keihin era big time. It was 36mm then though so it’s likely that on the 38mm carb you will need to be a step or two richer on the as a minimum.
 

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Discussion Starter #14
OK, so I have been playing with it this morning and giving it a blast the following setup absolutely rips
300 metres above sea level
Approx 10 degrees
Pwk 30
2017 ktm 300xc
42 pilot
178 main
3rd clip on needle
N3ch needle
Air screw 1 1/2 turns

Genuinely thought the mikuni was dialled in and may be disappointed with the results of the keihin, curiosity got me and I committed. To the keihin. So glad I did never ridden anything like it.
 

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Brilliant. It’ll only get better to as you dial it in. Nothing comes close to a sorted Keihin.

Mikuni just doesn’t have any finesse. Smartcarb, Lectron etc are just workarounds for jetting buffoons.
 
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The 300’s run a 36PWK before they went to Mikuni, there was a switch across the ranges from 38 to 36 on the enduro bikes, assume to add midrange. My old 200 runs a 38PWK, comes on the pipe like an overbored 125... good fun though.

I went 38 high velocity with the Lectron... but I know how to jet my bikes, I have other reasons for going down that route (large temperature and humidity swings). It also gives a better fuel signal like the STIC block does, bogs less and drinks less fuel as a result. Useful for running in soft sand, otherwise well set up PWK is fine.
 
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