Athena 170cc questions

[Calum]

@irongamer727 If the bike idles happily, and you pulling the throttle doesn't cause hesitance or bog, then the idle mixture is correct. I can't see the idle mixture increasing massively, but definitely should need to be notched up slightly.

For the running in period, you shouldn't actually need to up the main jet, as you should be hitting WOT. But I'd rather have it and not need it, than need it and not have it.

[Irongamer727]

@calum The bike is running a bit lean with stock pipe so I will definitely change main jet and adjust the needle. Too bad the needle only has 3 positions.

[Calum]

@irongamer727 Well needles are readily available.

[Irongamer727]

@calum any recommendations? Stock mikuni 28 dt125x 2005

[Calum]

@irongamer727 Yeah I'd recommend jetting it to suit.

I don't run that carb, the only experience I had with the Athena was when my brother ran it on his DTR and he ended up with a vastly too big 38mm Kehin Carb

[Irongamer727]

@calum so you don't think I need to adjust the needle that much? Rather finding a good jet?

[Calum]

@irongamer727 As said, it'll definitely need jetting accordingly, but it shouldn't be too far away with what you got.

Start with the idle, and work you way to part throttle, then once it's run it, sort out the full throttle.

But the stock jet shouldn't lean out the engine when running under part throttle.

The needle and pilot jets will affect this IIRC.

[Irongamer727]

@calum thing is. I'm most of the time driving around 1/2 -3/4 throttle. Not using WOT that much. And he is not running perfectly. Bogging a bit around 80 km/h. Definitely not due to an overrich mixture. The plug is, as I mentioned, still a bit too white. Previous owner did probably drill the main jet since it says 75 rather then the stock 210. I have now at my disposal proper Yamaha (mikuni) jets 260-290. Definitely needs new jets. Needle is set in the stock position in the middle.

[Calum]

@irongamer727 Drilling jets is a big no no. Never understood that myself.

Yeah I used to get this on my bike lol, always had to blip the throttle a few times to chuck fresh fuel/air into the cylinder.

[Irongamer727]

@calum Annoying as hell. That must be due to the jet right?

[Calum]

@irongamer727 Ah well, sorry it ran sweet, but my vapor gauge showed a huge spike in temperature lol.

Yeah it sounds like it's not jetted, or something else.

It's all vague and really would need to feel it to understand the probnlem

[declan]

@oldman you know how it is

[jackreece]

Ive got a 170kit on my dt125r can seem to get it to run right got a 360main in it and still doesnt run right went 280 to 300 didnt run right then 320 to 340 didnt run right so at 360

[Louis-DT-WR]

Just upping a main jet doesn't solve everything. There's more to it than that.
What other modifications have you got.
Condition of engine..
Did you fit the kit.
Was it brand new?
Was it running well before the kit was installed.
What exhaust.
What carb?
Powervalve set up and working?

[jackreece]

Its currently pinned fully rebuilt with exstended com rod wossner and flat top titanium wossner piston tm 32mm carb dep exhaust full system

[Louis-DT-WR]

Pinned valve doesn't perform well.
I'd put the standard carb back on and see how it runs with rejetting. I converted my 125r to 200cc. I run a tm34ss carb . And my dt200wr has the standard tm30ss (almost identical to the tmx30) both are good carbs for the bikes.
I did run a tm32 which never ran that well

[jackreece]

Its always ran better pinner electric pv just not very good on old ones on my newer one 2001 is fine with electric pv and i was using origanal tm28 carb it didnt like that with 170 kit

[Louis-DT-WR]

@jackreece show a picture with your tm32 installed. The float bowl needs to be pretty level. Because of how the DT engine and intake is, some carbs will sit at a angle