wr coughing and spurting 1/2 to full throttle

[yukondood]

wtf, i have pre filter, foam up and around seat, seems well sealed. might be carb icing and not snow injestion or perhaps engine running too cool and needs t stat? Does anyone run icypropyl?

Any toughts??

 

[powdermuncher]

Did that happen on the way over to my place with the ski

 

[yukondood]

nope

I'll dig it out and drop this week.

 

[tomk]

you are exactly right my wr did the same thing, I was out for the weekend riding average temp 15f or less and it was doing it, I used some plastic and made a cover for the carb that kinda ducted heat from the exhaust to keep it warm. not the best way to do it but it worked for the weekend

 

[M5-]

A buddy of mine just installed the KTM carb heater on his 2008 WR carb. He sent me some pics which I have since deleted but I will get him to resend them tonight and I'll post them up. On the WR carb there is an empty boss on the left side of the carb which he drilled and tapped. It turned out super slick and should work I would think. I'm going to figure out how to put one on my 450 KTM I'll have to machine a boss and attach it to the carb somehow.

M5

 

[Rush44]

Almost all of my popping and sputtering came from clogged vent lines. Make sure to re-route them up under your airbox.

 

[yukondood]

heated carb

M5 more detaisl and pics would be great. Spent the night pondering ideas to resolve anything from tubing form radiator to heated hand grip????????

 

[M5-]

here ya go.

M5

 

[yukondood]

sweet

M5, thanks, any chance you know year of ktm it came off- sorry I have no clue on ktm stuff and did your buddy wire to an off on switch or just full on circuit.

thanks again

 

[yukondood]

part number

http://motorambler.com/2011/03/review-ktm-carb-heater/ ktm part #55131003044, will give it a try.

 

[M5-]

These things are built for the 2 strokers but I can't see why it won't help the thumper as well. My buddy installed and wired his as per the instructions. He mounted the temp sensor in his airbox. He was talking about a manual electric bypass switch to be able to just trun it on and off, I'm not sure if he did that or not. I''m going to try and mount one on my 450 KTM but it's going to be trickier than on the WR carb. I'll post some pics when I get it done.

M5

 

[powdermuncher]

Hi Ykdood I have some Yamaha electric carb heaters of my old RX1 here that you can try -- thanks for the ski by the way.

Same Idea as the KTM ones.

Give me a call.

 

[yukondood]

carb

Pmuncher, I ordered a heater from cycle works, as per usual our local KTM/Honda/Doo dealer could barely pick up the phnoe let alone understand my request. Cycle Works was on it, knew what I was after and part will be here ASAP!!!

Glad ski worked out

 

[the sled shop]

good ideas i like to see custom carb stuff

 

[powdermuncher]

That looks Identical to the rx1 electric carb heaters.

Not sure if one alone will do it , but I know for sure they get hot enough to burn your fingers , don't ask me how I know

 

[CATSLEDMAN1]

wr snowbike evolution

, this fall I made some mods to my 2003 wr450. rode it today for 40 miles or so and had to cure all the missing.

. made two mods which will cause poor engine performance.

gutted the air box and made the box its self into a big fogz skin filter
put on quieter muffer

today went from 160 to 180 main jet...............wow, ran kind of ok first hour but some miss and hesitation on wide sweeping corners

fortunately I was riding with my pal Pearson on his new 010 yz450 mtn horse, toms jetted moreYZFs for Mx tracks the last twelve years or so than anyone I know.............so, jetting sol critical on these big 4 strokes, we rode both bikes, compared ideas, seemed lean, started putting in jets, up and up and up, running better all the time, can't stop till its fat and back off. Warm today and now spot on, pciked up a ton on low mid range, now some mid and low end improvement as we ride colder snow, we'll see.

but bulbbering missing hesitation now all gone. could have been bad gas, could have been rich, could be bad plug, fighting the the stock poor mid range ignition map, no........just jetting.

 

[yukondood]

180 too

did the same this afternoon up to 180. tomorrow will see if improved or not

 

[Cat Bandit]

What temp and elevation ate you guys running? My bike pops and farts up to half throttle, i think its fine above tho... My bike is an 09 yz with a slip on exhaust, and high flow intake... So far I've only gone up one size on the pilot jet, and its better. Should i try raising the needle? Or going bigger on the needle jet? I'm running from about 3 to 6 thousand feet elevation, and right near freezing, not too much colder...

 

[CATSLEDMAN1]

03 wr450

last sat when I was rejetting I was at Lolo pass west mont riding about 48-6000, last year on my wr riding 5-7000, once jetted there might have been some drop off in power but dead clean running pulling from low mid to high.

My Yzf 250 carbs are not as compliant on elevation changes, you have to be diddl'n that gas screw every 600ft of elevation change.