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Off idle bog out

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Ok I've bought this  2006 drz125 a week ago now for my daughter. Bike ran okish but doing research before I bought it i knew I was gonna do exhaust, air box mod, and rejet. Anyway bike had a FMF slip on with stock filter and air box and the plug was ok not white but not black either. So I ordered a new 22.5 pilot, 110 & 112.5 main jet along with a ttr125 adjustable needle. So I did oil change valve check complete carb tear down with new bowl gasket, accelerator diagram, main jet oring, float needle seat print, fuel hose you get my point.

 

Ok I started with 2.5 turns out from lightly seated on mixture screw, 22.5 pilot, 110 main, clip in middle groove.  Bike fired on second kick I adjusted the idle down (was WAY TO HIGH) AND it was GREAT! I drove around the yard up and down the street and then took it in the woods and it had a big when I twisted the throttle from a in gear almost at idle speed.... So I drove around nother five minutes same problem.

So I went three turns out no fix

Then I went 2 turns out no fix

Clip on top grove 2.5 turns got WORSE with backfire on deacceleration.  Went to 1.5 turns same problem. 3 turns put backfire is gone bog is still there!

Now I'm at third groove closet to the point 2.75 turns put bike fires right up idles perfect BUT when I full twist throttle at idle or in gear barely moving it bogs to a almost stall! New plug is white like it's lean still?? 

I know add two small washers under plastic spacer on needle to raise it up, problem with bog is still there.....

 

I'm going insane what should I do now? I have a bigger 112.5 main but I always though the main is for 1/2 to wide open throttle? FYI too end is PERFECT wirh no sputter spits or anything! So now I'm back to the pilot which I can go back to the stock one but that would lean me out even more correct? Or do I try stock needle with 22.5 pilot jet and add spacer to lift it up more?

I'd like this fixed today as I'm suppose to take the kids riding to.orrow morning and my daughter is on my rear to get the bike ready for her LOL

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ok that's the plug right after I added spacers to the needle which was just WHITE! I'm done with this I hate little bikes......so now what it seems I'll have to add the stock pilot and play with the needle clip and fuel screw......

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Added new plug and went with stock pilot, removed shims and put yahama needle at third clip 2 turns out and mixture screw...BIKE RUBS LIKE CRAP it wouldn't start it won't idle correctly, when I rev it it hangs up and then idles down SLOWLY put it in gear and give her throttle and it bogs worse than before and pips all the time!!!! 

Went three turns out which helped popping I was getting, went to middle groobe on clio and revs still hang up and bog is horrible 

So now I'm gonna add the 22.5 pilot again and stock needle and try 2.5 turns in mixture screw and see what happens...

 

FYI I'm using larger 110 main jet like I mentioned above, could the main be too small?

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Put the big lot in make sure it starts and idles nice . sounds like you had that correct. Now it's been a while since I've had a stock carb apart on one of these things but seems to me there are more parts with that needle than a regular Mikuni on a big bike and they can go together in the wrong order . Make sure you have all the bits in the correct order according to a Suzuki diagram. 

 

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The little white plastic ring goes under the needle clip and I think it's brass goes on top of the clip .  I've had them backwards before it doesn't work like that.  

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I have that correct, plastic spacer then clip then little washer then tiny spring then top white plastic retaining clip that the big spring goes on under the carb top where the cable is

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Ok I went back to the 22.5 pilot jet, I'm 2 turns out on mixture screw, I went to the larger 112.5 main jet i bought and I have the Yahama needle set correct way with clip in middle groove

Bike fired right up on first kick,  I adjusted idle and it's PERFECT again, no surging or hanging. Then drove it up and down my street and around the yard till it warmed up....NOW it's running perfect on wide open runs in all gears, no problems, completely let go of the throttle and I have no pops or backfiring. If I'm running hard around the woods or down the street and up shift or down shift with the motor racing up in revs the bike just takes off with ZERO issues 

BUT 

if I let it idle down to normal and twist the throttle I'm still having a bog, not enough to stall the engine but a bog! If I come into a turn and drive it like my drz400e or rmz450 (gear high,  then only use front brake slightly and down shift right before a burm or tight turn and then throttle into,  through and out of said burm or turn the bike is OK... the motor pulls for me weighing 200lbs BUT if its a super tight turn or im not perfect with the rpm the bike bogs if i twist the throttle hard! 

What now? Mess with the needle again go up or down? Or do I play with the mixture screw again?

OR is it a main jet issue because the bigger 112.5 main has the bike running the best so far?

Edited by superdutyscaler

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leave everything the same just move the clip one groove down on the needle.  Likely your daughter won't be wacking the throttle open at the same speed you might be and she'll never notice the bog.   

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One groove down would be closer to the pointed end yes, and that would give more fuel to help the bog?

 

And why is there still a bog I understand it doesn't have the carbs my bike bikes do but it shouldn't be getting this especially after reading post on here?

 

 

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This is with stock pilot 110 main third groove down closest to point end..its too lean

 

 

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This is 22.5 pilot and 112.5 main with needle at second groove...its a little better but I feel it's still too lean and like I said I have the bog if I let the engine idle down and then try to twist the throttle hard

Edited by superdutyscaler

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keep going richer with the needle . Move the clip down (towards the pointy end) or if you have some shims you can shim the needle just make sure you don't raise it so high the it comes out of the needle jet and hangs the throttle open.  The needle jet and the jet needle work together at some point a different shaped needle may be required or an altogether different needle jet ( I call them nozzle to avoid confusion)  How ever I'm not sure what's available for these carbs in that area if anything.  Also in the range you're having trouble with the slide cutaway could be changed. Again not sure what if anything is available for these carbs and if parts are available the cost might be better put towards a bigger better carb.  

If you figured it needs more fuel still down low you could trim in a late the bottom of the slide maybe .010 at a time to see if it helps .  

  https://www.howtomotorcyclerepair.com/how-to-tune-throttle-valve-cutaway/

It's never going to work like a Keihin FCR or a carb with an accelerator pump.  

 

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Ok I'm gonna raise the ttr125 needle to the lowest setting towards the pointy end and see how it does. I rode it around yesterday again and it has the bog that's driving me nuts! And yes I understand it's not gonna react like my two big bikes but man this thing almost goes flat dead if i twist the throttle wide open. I've ridden 4x4 quads with basic carbs that don't do that?

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These things are pretty sickly in stock form complete with a heavy crank and flywheel and low compression even with carb correct that poor thing might not be able to rev up quick enough to keep up with a snap throttle open ???  Let us know how moving the needle works.

 

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