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pete.ktm
13th March 2018, 08:53
Hey

Got a 2011 KTM 300 EXC, over the last few months I've been noticing the engine occasionally missing/stumbling while accelerating.

Have been re-jetting (unsuccessfully) trying to get rid of it and then on a recent ride it sort of struck me that it's only on uphill's that it stumbles.

Last weekend I checked the float height and raised the fuel level by a mm or 2, but on the ride it again started to miss while going up a moderate gravel hill accelerating in 5th and then when the hill flattened off and I accelerated again in the same gear the bike just took off, smooth as.

Any ideas?

Cheers

awayatc
13th March 2018, 09:06
Have you checked fuel filter (s)?

Akzle
13th March 2018, 17:54
and give it a new plug

george formby
13th March 2018, 18:17
Carb breather pipe?

Does it happen on reserve?

pete.ktm
13th March 2018, 22:49
>Have you checked fuel filter (s)?

hasn't got a inline type of filter but i'll take the fuel cock off and give that a clean. but gas seems to piss out ok when i've had the fuel hose off and turned the tap on. guess i'll have to get the tank at the right angle to simulate climbing a hill to notice if theres a problem.

>and give it a new plug

it's had 2 new ones since i've noticed the problem. wouldn't have thought a plug would be effected by the bikes angle?

>Carb breather pipe?
>Does it happen on reserve?

i put new breather pipes on before the last ride but didn't check for a blockage, duh, will do that. i also route two up to my air box, might try putting them back to standard setup. Will try reserve next ride.

Cheers for the ideas.

Akzle
14th March 2018, 08:32
>Have you checked fuel filter (s)?

hasn't got a inline type of filter but i'll take the fuel cock off and give that a clean. but gas seems to piss out ok when i've had the fuel hose off and turned the tap on. guess i'll have to get the tank at the right angle to simulate climbing a hill to notice if theres a problem.

>and give it a new plug

it's had 2 new ones since i've noticed the problem. wouldn't have thought a plug would be effected by the bikes angle?

>Carb breather pipe?
>Does it happen on reserve?

i put new breather pipes on before the last ride but didn't check for a blockage, duh, will do that. i also route two up to my air box, might try putting them back to standard setup. Will try reserve next ride.

Cheers for the ideas.
heat. load.
coils tend to fail when hot. weak spark becomes no spark..

F5 Dave
16th March 2018, 20:01
The hill thing may just be increased load, especially when raising the float level didn't help.

You will likely find on forums some jetting advice while not always 100% for our fuel, identifies which needles don't work. Right needle or you're wasting your time.
identify where the stumble is. But think in throttle position not revs. Write this down on some tape on your tank.

I've had issues with very steep hills but been cured with float adjustment.
Obviousy things like coils plugs and plug caps can break down. Check coil connections and earth.

pete.ktm
18th March 2018, 21:10
you guys might be on to something.

got two minutes into the afternoon loop and the bike dies. no spark.

looks like coil, stator or cdi. hopefully related, but more like just my shitty luck.

cheers

sidecar bob
19th March 2018, 09:19
Your bike has insufficient strokes. Have two more strokes installed & the problem will dissapear.

Crasherfromwayback
19th March 2018, 09:56
Your bike has insufficient strokes. Have two more strokes installed & the problem will dissapear.

He'll have to add ten kilos too then, and lose a 1/3 of it's power.

F5 Dave
19th March 2018, 11:57
And refuse to start when dropped until you have lost the will to live or ride any further. 20 km from the end of the loop.

pete.ktm
19th March 2018, 21:47
And refuse to start when dropped until you have lost the will to live or ride any further. 20 km from the end of the loop.

ha ha i was lucky, with a few downhills back to the car park it was a pushable distance.

335789

just measured my stator and the exciter is 9.8ohms, it should be 12.7 +- 15%, found another thread where the guys was reading the same and his shop confirmed it was stuffed.

hope TSS arn't busy this week. yeah right.

F5 Dave
20th March 2018, 06:07
Heat it up and see if it changes drastically.

husaberg
21st March 2018, 21:22
just measured my stator and the exciter is 9.8ohms, it should be 12.7 +- 15%, found another thread where the guys was reading the same and his shop confirmed it was stuffed.

hope TSS arn't busy this week. yeah right.
Ricky stators and Electrix world do them
Pretty sure some of the Katies are the same as a CR250 Honda.
About $120 US last time i looked
Some crowd out of aussie i think had aftermarket ones of TM as while back as well.

pete.ktm
22nd March 2018, 12:43
Ricky stators and Electrix world do them


Thanx, trail tech do an after market one for $US175.

So i got one of those coming BUT TSS say theres a OEM one in Auckland for $NZ500.

So if it does turn out to be the stator i guess i gotta decide how badly i want to ride next weekend (unless DHL gets that trail tech one on the fast plane).

Cheers

husaberg
22nd March 2018, 13:38
Thanx, trail tech do an after market one for $US175.

So i got one of those coming BUT TSS say theres a OEM one in Auckland for $NZ500.

So if it does turn out to be the stator i guess i gotta decide how badly i want to ride next weekend (unless DHL gets that trail tech one on the fast plane).

Cheers
$500 buys a lot of petrol
Looks like the older pre electric start ones were the similar ones a used by honda. 25 watt or so, rather than 100w ish for the later ones
Because the early aftermarket ones are cheap.
https://www.trademe.co.nz/motors/motorbikes/parts-for-sale/electrics/auction-1574781253.htm?rsqid=4c9887f27a854be098d48b17d4e87 5d5

pete.ktm
2nd April 2018, 13:54
ok, new stator and the bikes got spark again, but it's still missing.

mates sending me a another carb to try and i'll probably get a new coil.

if that doesn't work... well it'll be winter and it can sit in the garage for a couple of months and think about it's attitude!

husaberg
2nd April 2018, 14:08
ok, new stator and the bikes got spark again, but it's still missing.

mates sending me a another carb to try and i'll probably get a new coil.

if that doesn't work... well it'll be winter and it can sit in the garage for a couple of months and think about it's attitude!

is the plug cap a good fit no wobble at all?

pete.ktm
3rd April 2018, 15:56
is the plug cap a good fit no wobble at all?

yeah seems to be a good fit.

everytime i have the carb off i forget to check the reeds so will do that when i change over to my mates carb. but most symptoms of bad reeds include hard starting and mine starts 2nd kick from cold when the air screw is right.

so it's new carb/check reeds, if no improvement new coil/spark plug cap.

pete.ktm
5th April 2018, 22:42
now i'm no mechanic but i have a feeling this is not how they came from the factory lol

my mate only told me 3 times to check the reeds.

336019

F5 Dave
6th April 2018, 07:00
My H100 would misfire when it chipped it's Yamaha reeds . But started easily.

pete.ktm
6th April 2018, 21:29
My H100 would misfire when it chipped it's Yamaha reeds . But started easily.

yeah now every search i do points to reeds as a possibility, where have you been for the last year google?!?!?!

pete.ktm
9th April 2018, 13:39
i can officially close this thread. had a ride on sunday and the bike now rips, feels soo different.

made a note to change reeds every 50 hours.

thanx for all your help.

Michaelpum
28th June 2018, 08:19
Looking for anyone around the Kentucky area reletively close to do some gravel roads and or trails with always looking to make friends. If anyone knows any good places to go in ky, in, oh, for now would awesome.

awayatc
28th June 2018, 08:40
Looking for anyone around the Kentucky area reletively close to do some gravel roads and or trails with always looking to make friends. If anyone knows any good places to go in ky, in, oh, for now would awesome.

Is that in the North or in the South island?

There are a few Ketucky fried chicken places around these days

F5 Dave
28th June 2018, 17:26
Is there a bank account we can send money?

And I do believe there was some mention of a princehood.

Virago
23rd July 2018, 21:06
Looking for anyone around the Kentucky area reletively close to do some gravel roads and or trails with always looking to make friends. If anyone knows any good places to go in ky, in, oh, for now would awesome.

You could check in with this guy:

http://forums.offroadtb.com/viewtopic.php?f=11&t=6697