[thisone1]

Guys
bought it from the previous owner who kick started it but took quite a few kicks.
I brought it home and it was sitting in the garage for more than a month. Finally got money to fix it.
shimmed the valves and are in spec. in-.15mm ex- .28mm.
timing is lined all three spots. flywheel, cam, crank.
pulled the carb out and replaced all jets, cleaned it twice.
disconnected the kill switch.
replaced the spark plug, resistance 4.56ohms
IG resistance 12.89ohms.
spark plug sparks light blue everytime when it ground it and kick.
fuel is squirted every twist.
after 20 kicks it backfired with a loud pop.
emptied the fuel by shaking it with a stabilizer. let the tank dry and put in new 93 octane.

haven't tried to bump start it yet.
still doesn't start. please help; haven't even ridden once on the bike.

[JimDirt]

Welcome to the site !!

What you did not mention was Compression , if it does not have compression it will not start no matter what is aligned .... you should have (kick engine over until gauge stops moving maybe 5 or more kicks with throttle wide open) about 78 psi , also , have you confirmed the Decompressor is working and not stuck open , as it could be holding the exhaust valve open and it will drop compression as well .....

Also if the prior owner lived/rode at a higher or lower elevation (a couple thousand feet different) , the jetting may be off enough to not allow it to start ..... try this , take a hose like the vent line to the gas cap .... dip it in some gas about 4 or so inches in , then place your thumb over the top hole , pull it out and stick it in the plug hole (obviously have the plug out first) then remove your thumb from the line , the gas will go into the cylinder , then put the plug back in , and try to start the bike , this will tell you if it is fuel related or not , but I am suspecting it is a compression issue , but jetting could be off if the elevation change was dramatic enough ..

[thisone1]

Thank you Jim dirt.
I ordered a compression testing guage and a new cylinder head gasket. While I'm waiting on those. I will do these tests and report back.
1. Checking the decompression plunger to see if it moves when I turn the weight.
2. Add fuel in the spark plug hole and try kicking it.
3. Glad u mentioned evlevation changes. I'm going to set the AF screw to factory setting and will try to kick start.

[thisone1]

okay here's what I've tried.
1. put the engine to TDC and tried to move the de-compressor weight with my thumb; It did move the plunger back and forth.
2. after card rebuild I noticed that i set AF screw to 2 3/4 turn instead of 1 3/4 per manual. drained the fuel and adjusted that.
3. added fuel in the spark plug hole

tried to kick it over, now it wanted to start maybe 2 thumps.

Pressed hot start twice and kicked, it started for may be 2 secs and died off. Another kick same thing.
and then nothing for further kicks.

[JimDirt]

Ok , what you are describing is a fuel issue , since when you poured in gas it fired , so now you have to see where the blockage or restriction is , how about Float Level ?? , have you adjusted that ??? , it should be 8mm from the flat surface of the carb body holding the carb sideways with the pin to the float up .. Start with that ... if that is good , it may have a internal blockage , Try a different starting procedure ... Try pumping the throttle 6 times , then full choke , then kick , but only kick when the bike is on full compression .... so rotate the engine slowly with your foot till you feel it get hard , then give it a full hard kick doing the throttle procedure I mentioned , it hopefully should start ...

[thisone1]

Okay, I'm pulling the carb out. Will report back.
I really appreciate your help

[thisone1]

After pulling the carb, I noticed that the jetting ie off.
Per 07 service manual:
Pilot screw : 1-3/4
Slow Jet : 42
JN Clip : 3rd
Needle : NJYR
Main Jet: 178

What I found in the carb was:
Slow Jet : 42
JN Clip : 3rd
Needle : NJGR(appears to be OE needle for 08-)
Main Jet: 175

I can understand why the main jet is 175 since we're in Texas(79F-100F) but do u think that the needle is making the congestion?

float size is 10.5 mm

07 manual says float is 6mm but you and YT videos say 8mm? Which one shall I set it to?

Not sure the difference between the needles NJGR vs NJYR but I guess I'm better off using the prescribed needle.

Thanks for isolating the issue.

[JimDirt]

Not sure why the 07/08 is different , but usually it is 8mm ... but I just looked at my 07-08 Service Manual , and my 07 Owners Manual , and my 08 Owners Manual, and they all say as you mentioned , 6mm , so go ahead with that , but yea ,10 is way off ...

Is the Fuel Screw still at 1-3/4 ? , and the difference in your jetting is not far enough off to cause any major issues , at least not like you are having , the float level may be part of it , but not sure if it would cause all the issues .... , I think you still have a fuel delivery issue ... , and having to use the Hot Start bothers me as well ... I am hoping Leardriver chimes in , as if anyone would know for sure it is him ...

Also don't forget to try the starting procedure I mentioned , see if it makes any difference ...

[thisone1]

Thanks JimDirt, you nailed the issue. It is indeed fuel delivery.
Pulled the carb out and immediately went for the air passage since that is the only thing that would stop the venturi.
Well, what did I not see/think when I cleaned the carb twice earlier. The slow air jet is clogged to the core.

Cleaned the air jet, while at it also took the AC pump bypass and cleaned that Jet as well.
Adjusted the float to 6mm. AF screw 1-1/2 turns. Cleaned, dried and oiled the air filter.

Put everything back to together.
Primed 6 times, TDC, kick, small hope that engine is going in the right direction.
Choke on, TDC and kick, nothing.
Another Prime, Choke off, TDC and kick started for 10 secs and died.
Prime 2 times, TDC and kick fired right up. Ran for a good 45 secs and when I went for the throttle, it died.
Idle screw in 2 turns(Clockwise), TDC and kick, fired right back up with little high rpm(idling). Adjusted the Idle screw a 1/4 turn back out and any more than that it starts choking. Ran for a min, throttle response is good. Killed the engine.

Wanted to see that is not just a fluke and tried to kick it again at TDC, nothing. Pulled the hot-start in, TDC and kick, fired back up right up. Is it normal to use the hot start even if the engine ran only for a min?
I'm thinking to puton a radiator temp gauge cap and tach/hour meter.
Also the previous owner didn't mention anything about the last re-build and I, in my excitement in buying my first dirt bike after riding on a buddy's 12 years ago didn't even ask him.
Considering that the bike will only see trails once or twice a month for an hour, when is a good time to do a full re-build? Is it necessary now?

I wanted to let you know how thankful I am to you in get this resolved. I was doing track 12 years ago and then life happened. This is my re-entry back to dirt(I have always been riding street and MTB all this while though) and hopefully will get back to track when I muster the cash to get all the gear but that will probably be on 125 2-stroke.

Tried to put in detail everything that I can think of just so If any one goes through the same issue, hopefully this will help them.

[JimDirt]

OK , good to hear it is somewhat running , what you want to do is to get the Fuel Screw (air screw only on 2 strokes) as close as possible to spec , the farther you screw it in the leaner you are making it , so you need to go DOWN on the Pilot ,OR easier and better would be to go UP one on the Needle Clip position to 2 instead of 3 , this will lean it out on the bottom slightly but not affect the top end fuel delivery

So try the Needle position first , then see how close you can get the the OEM screw setting ... that is the ultimate goal , is to fine tune the system to work within the specs , a 42 should be lean enough , so working with the Needle will fine tune the bottom , since you say when touching the throttle is when it coughs , so it is getting too much fuel initially , the issue is on the bottom end of throttle , as the Hot Start is literally what it says , it is for starting a HOT/WARM Engine where you do not want a rich mixture , so it leans the system by adding more air , so your carb is telling you it is too rich on bottom end ... and you need to lean it to make the mixture where it should be .... on a side note , if your air filter is heavily oiled , or a thick oil is used it will richen the system , so keep that in mind when tuning ...

[thisone1]

okay, tomorrow I'll will try these 2 settings and report back.
1. AF screw 1-3/4 (factory setting)
When you say go DOWN on the pilot, do you mean higher number? I only have 45 on hand. If that is not it,
2. Only then try clip position 2.

Let me know if I misunderstood anything.

[Aussiecrf230]

The next size down on a 45 pilot would be a 42.
When you adjusted your fuel screw gently back and forth to get peak idle speed, how many turns from gently seated did it end up?
That will help determine which idle jet.

[JimDirt]

okay, tomorrow I'll will try these 2 settings and report back.
1. AF screw 1-3/4 (factory setting)
When you say go DOWN on the pilot, do you mean higher number? I only have 45 on hand. If that is not it,
2. Only then try clip position 2.

Let me know if I misunderstood anything.

Like Ray mentioned , next DOWN as in lower number to a 45 which would be a 42 , which would be stock ..

If you have to turn the fuel screw in to 1 or less turns out , you need a smaller (lower number) Pilot , if you need to turn it out more than 3 turns , you need a larger Pilot , and don't force it closed , or you will damage the tip , turn it till there is resistance and it is lightly seated , then turn it out counting the full turns and/or 1/4 or 1/2 turns

[thisone1]

Thanks guys, I haven't gotten time since Sunday to check on this. I will put in 42(stock) and set the screw back to 1-3/4(stock). I've since also got a tach/hour meter. I will try to adjust it to around 1700 rpm after warming up the engine will report back my findings.

[thisone1]

Okay, got 42 in, AF 1-3/4. Installed tach meter and was surprised to see high idling.
3400rpm. Any less than that, engine is stalling and will not start. Any help here?

Also I hear clicking noise when the engine is running. Are the valves gone?