ADVICE on my first 4stroke/Kawi **PICS**

Thanks for taking a look,

I would really appreciate any and all comments, short or long

I also appreciate any of you able to make it thru this entire novel.


i have been around on this fourum for a bit, however it was a year ago and forgot my login info, so this is my new one..


Anyway, Ive always had 2-strokes my whole life, and rode my friends crf450 and immediately wanted to get a 4 stroke.


So here it is, Its not fantastic by anymeans,

 2007 Kx250f

full fmf

protaper triple

some weird green rims, (I dont hate them)

some sort of holeshot device on the fork


Im a novice, yes i have been riding for 12 years, so i can easily hop on any bike and ride it but not a pro by any stretch,

I have owned a few yz125s and 250s (2strokes)


here are a couple questions I have on this bike


previous owner was not a kid, or abuser who was irresponsible, but he did seem like he was a hard rider, however did keep up on common maintenance after each ride.


The main issue I need to fix before I can do any serious riding is i need a new or rebuild Rear brake master cylinder.. previous owner said I could find a used one off preferrably a newer kx250f instead of buying new, or I could rebuild the one i have I think i have the body for it,, I also do have the line too all is disconnected, the pin is barely or not even touching the disc when rolling. heres a pic




What should I do on this? If its not too much more expensive (and as a novice mechanic as well) on a scale of 1-10 how difficult is this project, assuming i could find some videos on youtube, I think i can manage, should i rebuild? just buy a new one? I believe new its like $2xx.00 or so, and used on ebay less than $20-$50 or is it tricky enough to need to use one of my mechanics in the area (not with a company, hes very affordable) just a hassle to take it over.


next is the throttle seems to stick a little, the previous owner said i should lube the throttle cable, is this the usual suspect to that, or is it the throttle tube? he put on new grips recently so I am assuming the tube isnt too bad, if lubing the throttle cable is the answer, im sure that is easier to find online as a tutorial, or is that something pointless and I should just buy a new one..


I have noticed the Kick start lever does have a bit too much play only when in the upright position after starting, i can easily move it to where when in the up position, it can wiggle and rattle against the frame.. what should i do there, just put some soft foamy tape against the frame in that 2 inch section and leave it be? or is it something needing to be fixed asap

compression is really good, starts up easily


When I fired it up today, i smelled a scent that seemed like a burning smell, definitly noticable, does have me worried, I looked down and where the pipe comes around the rad, it was red from how hot it was, (within 2 minutes of being started up, not riding, just idling letting it warm up) I know these pipes get hot, but should it turn red like an iron in the fire? scared me a little too..


lets see.. whats next..

lastly, when starting it up today, and riding very briefly yesterday as a test ride (yes with no rear brake) it did do some backfiring (not often, but a couple times) and today i did notice some very very brief Flames coming out for that split second flash.. googles that and seems its not too uncommon, please let me know what to do on that too.


as a first time 4stroke owner, I think ive heard usually the most expensive thing to fix is the valves or reeds or something my buddy was saying.. DOES ANY OF THE ABOVE ISSUES SEEM LIKE THAT COULD BE THE CASE?

if so, i may take it to my private mech to do a rehaul




I am in process of a full cosmetic facelift.. usually the first thing I do on any bike I buy to make it mine,

I live in Corona CA, so i today I had the luxury of walking into procircuit today check out the showroom, and check things like my kick start lever, etc..



overall, the bike runs pretty well, it idles good, the clutch seems very good and tight, seems very quick, I dont really know what to compare it to other than my 2 strokes, even with these issues I think i have a new favorite bike.




well seems as though I have my hands full on doing some fixin' (which i dont mind at all I kinda enjoy (it the issues i can fix that is)), however being unknowledgable and somewhat uncapeable on some of these issues stresses me out and I really value the advice and opnions of you all on here, i read everything i can, and really really appreciate any advice you can give me.



heres your kids future competition haha thanks again for reading and feedback






I'll help ya with one thing ..... Sounds like the glue he used slipped down from grip to throttle tube/bars.... I would take of grips... Throttle tube and clean everything thoughly.... Then put on grips of your choice... If that doesn't do it lube cable.... Sounds like to much glue though....

nice bike , needs some tlc

rear brake master is very easy to disassemble and reassemble. The crapper is bleeding the system.

It will take a bit of time since the piston is small.

kick start assembly has a allen head set screw that you can screw in to tighten up that play. I would lube it well and then adjust it.

the backfire usually comes from being a bit lean. Possibly need to take the carb apart and make sure all the ports are clear. Especially the pilot jet and the port to it.


The backfire usually comes from an unsealed head pipe and double posted topics are always annoying.

The backfire usually comes from an unsealed head pipe and double posted topics are always annoying.

Thanks and sorry as I did not know what category to post under, notice how many posts I've made?

Those expecting newbies to post as grizzled veterans is more annoying imo but either way I've valued your responses

Thanks and sorry as I did not know what category to post under, notice how many posts I've made?

Those expecting newbies to post as grizzled veterans is more annoying imo but either way I've valued your responses


Holy crap, that's funny!  Grizzled is right!  Believe it or not, I was not blaming you or anyone for the double post, but I see that my grumpiness came through . . .  :devil:


The fact that you valued my responses is nice   :thumbsup: I am sure we will all carry on.  Back to your other topic to see how you are doing . . .

Sounds like the bike is running lean. 

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