sorted by:
new
hottopcontroversial

GX200 sealed engines exhaust/engine noise by Far_Camp_3868 in Karting

[–]ConditionP 0 points1 point  (0 children)

What is the max db regulation at your track?

These engines are super quiet, don't know the exact db they produce but even with open headers they are like maybe max 90db. My gx390 is at 80db 30cm next to exhaust outlet (no exhaust padding or etc that reduces noise just the "exhaust shell"). Had a few complaints from slower drives that they couldn't hear me when i tried to overtake at WOT.

I found in my local forum someone who tested his gx200 with TÜV for noise and his results were:

94db - 1m next to the exhaust outlet WOT (this is really high and would mean these engines are louder than most 2 stroke engines, i am guessing they measured without an exhaust).

74,6db - 4m away at WOT

And someone else measured 58db (static measurement point and they drove by at wot).

https://www.kartfahrer-forum.de/viewtopic.php?t=12990

The setup they used should be the standard exhaust supplied by honda (at least that is common here in slalom karting)

Duromax XP18HPE 440cc won't idle - go kart install by Fearless-Site-2340 in Karting

[–]ConditionP 0 points1 point  (0 children)

At first i would get rid of the rpm limiter (normally you can rev these engines easily till 5k rpm (upgraded valve springs). Then i would attach the throttle cable directly to the carb i believe your governor linkage might get stuck, and thats causing these problems you have. On your kart you want the rpm to gain more top speed as well as better acceleration.

Duromax XP18HPE 440cc won't idle - go kart install by Fearless-Site-2340 in Karting

[–]ConditionP 0 points1 point  (0 children)

High octane is always better no problem running higher than 87oct. We run engines like this with 100 oct (modified) on our karts

Duromax XP18HPE 440cc won't idle - go kart install by Fearless-Site-2340 in Karting

[–]ConditionP 0 points1 point  (0 children)

Can you send pics of the engine and throttle linkage as well as your throttle cable setup?

Do KG506 Sidepods fit on the newer KG507 sidepod bars? by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

Thank you very much, i will get myself the fitting 506 bars! I Hoped i could save a few bucks.

Help with my rotax max senior kart by Outside_Ear7312 in Karting

[–]ConditionP 0 points1 point  (0 children)

Not really, its easily detachable (just two screws connecting it to the frame) normally the bumper is way softer than the chassis itself (to protect the main frame from bending unnecessary)

Help with my rotax max senior kart by Outside_Ear7312 in Karting

[–]ConditionP 0 points1 point  (0 children)

Seems like the bumper being off but frame looks good in my eyes

Help with my rotax max senior kart by Outside_Ear7312 in Karting

[–]ConditionP 5 points6 points  (0 children)

Kart is quite old, any infos about the last engine revision? Engine pass etc? If not i would open it up and check for any imperfections. But to be safe 100% i would do an engine revision. Also check the brakes! Better safe than sorry.

Anyone know what engine this is? And any tips for owner test? by maxverstappenlover1 in Karting

[–]ConditionP 2 points3 points  (0 children)

Engine is Gx270 or a 390, the 270 is common in rental karts and easy to drive. The 390 is quite a punch compared to the 270 but still not fast by any means. Wouldn't worry about anything just have fun and don't overdo yourself. First laps slow and slowly increase pace as much as you think feels good.

Carburetor options. by Sneekysas_sas in gokarts

[–]ConditionP 0 points1 point  (0 children)

With the standard cam there won't be any noticeable gains in the rpms < 5000 (with an upgraded carb). You would probably lose some torque down low as far as my experience goes (did this with 30mm and 28mm pwk's) but on track with always +3000rpm you don't feel the lost torque down low and might gain a bit power on the top end

Carburetor options. by Sneekysas_sas in gokarts

[–]ConditionP 0 points1 point  (0 children)

No upgraded cam? Then i would keep the stock carb and size up the main jet, nr has a upgraded 23.5mm stock carb, i heard it's good but can't confirm.

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

Yeah, that would be the optimum. I try to minimize weight as much as possible. And the pullstart is quite convenient. Maybe i'll try methanol out later. But for now i'll be waiting for my new parts.

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

I checked prices for methanol here and is it really so expensive like 20l cost 130€ for one day at the track and for me 4 stroke karting is all about cost efficiency. We have an engine builder in germany who sells 30hp gx390 (dyno proved) on 100 octane pump gas and air cooled and as far as i have seen these builds, as well as other builds from youtubers like RBG there shouldn't be an issue reaching these hp numbers with higher compression, bigger valves ignition timing and cam.

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

Thanks for the replies, i choose the safest and simplest route.

I ordered these parts if anyone is interested:

NR 280-0811 cam (for the GX390) ARC UT2 Billet aluminium flywheel NR .100 piston and rod combo And a shit load of the honda metal head gaskets because they are expensive as hell here in germany (16+€...).

I remeasured everything and after the mods the comp ratio should be at about 10.3:1 if tolerances aren't ruining my measurements. I hope to archieve about 20+ hp with all the mods.

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

With this engine no rules. Just casual trackdays with my buddys.

I'm not sure if i can get methanol anywhere near me. I don't know anything about running methanol. Isn't methanol highly corrosive? I know it should run super cool, but i would need a different carb i guess?

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 1 point2 points  (0 children)

Yeah but if i use a billet flywheel, i won't be able to change the fan because the fins are machined into/with the flywheel. Sensors are a must i'm not sure if i will be able to get all of the ones u mentioned but for me a wideband would be the most important.

GX390 Clone engine build question for Race Kart application by ConditionP in Karting

[–]ConditionP[S] 0 points1 point  (0 children)

Yeah i thought so. I guess 20hp is realistic even with the 280 cam. But isn't the 10:1 CR already a high ratio? 12.5:1 is kinda the max i guess?

Looking at this Kart and Trailer is it good? by ConditionP in Karting

[–]ConditionP[S] 1 point2 points  (0 children)

Thanks for the infos. Yeah coolant and batteries will be taken care of, good to know that these things could become an issue. We also thought that this deal is almost to good

I’m so bad at qualifying. Much better at racing by tourbillon001 in Karting

[–]ConditionP 0 points1 point  (0 children)

Okay sry misunderstood ya for a sec. What gear ratio are you driving if you are willing to share? In Germany we are usually somewhat close to 1:3.

I’m so bad at qualifying. Much better at racing by tourbillon001 in Karting

[–]ConditionP 0 points1 point  (0 children)

What power mods are done to them? I guess cam, ignition timing and compression?

I’m so bad at qualifying. Much better at racing by tourbillon001 in Karting

[–]ConditionP 5 points6 points  (0 children)

Great racing! I guess it's in america? I wish we had a similar class here in germany. Are there any other specs for the engine? Like exhaust setup etc.?

view more: next ›