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Discussion Starter #1 (Edited)
I have it running pretty well the past couple days finally. Carlos had set up the carb with a # 165 MJ (included a 162 also) and a # 52 pilot (included a 50 also). The DGH needle was set in the middle notch. It was way rich at idle with the #52, and would only idle when cold, even with the airscrew like 4 turns out. I went down to a #45 I had on hand, and at 2 turns out on the airscrew, it idles pretty well, but is still a bit rich (still didn't need choke to start when cold), so I have a #42 coming that should put it in range.

The quick spin I did the other day, the 165 MJ seemed a big boggy (but I didn't get to ride it much at all), so I put a 160 MJ in with the 45 PJ. I rode it at speed, for the first time today. It seems to run very strong at full throttle and maybe a bit soft through mid range throttle. One thing I did notice, was after making a full throttle run through all gears, then slowing, downshifting, and turning around, when getting back on the gas, it seemed like it was bogging down, like it either was loading up, or the ignition was going flat. I think it was fuel related bogging, since it did clear up after a few seconds on the gas, and since it had been running strong at full throttle. When parking it, the cylinder wasn't overly hot, but pretty warm to the touch, and warmer than I would have guessed, since it was 34 degrees out, and I had putted it slowly, for about an eighth mile, to bring it back to the garage.

So, I guess my plan is to maybe bump the MJ back up a notch to a 162 (the heat concerns me a little), and lower the needle, and do some more testing. I know I need to do a plug chop, but I want to get it close by seat of the pants before doing that. Any thoughts on the bogging or power loss (it almost felt like I had left the gas valve off, and it was cutting out as I hit the gas) after slowing and downshifting from the open throttle run through the gears? Needle too rich cause that? I also have an inline fuel filter.... could that be restricting fuel fast enough that the bowl was to empty, until recovering?
 

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Jim,

If she is Rich, then re-ject each circuit starting with the Pilot, Main and finally Needle. The carb came jetted on the Rich side purposely, better safe than sorry.

As far as how the carb was shipped; The AS was pre set at 1 1/2, BPS at 2 1/2, DGH needle on the 3rd clip from top, 165 Main & 52 Pilot. Get the idle set correctly first, keep going down on the Pilot until youmget a crisp throttle responce of idle, good idle pattern, and your AS is between 1 1/2 to 2 turns out.

Once the idle is set, work omn the Main....first listen to the engine at WOT in 5th gear, run open WOT streches for 7 to 9 seconds listening for a WOT breakup; this could be a Lean or Rich setting. Once you dial the Main in close, perform a series of WOT plug chops for final tune of the Main....as an example; if shes Rich with the 165, go down to the 162, then 160, until she cleans up, then go one jet size up.

The needle will be your last jet setting to determine, the DGH we installed is a relatively Rich needle, it is a good safe 1/4 to 3/4 throttle needle. If she breaks up or is running lean at 1/4 throttle, go Richer or Leaner on the needle diameter, this is the last letter 'H', if the 1/2 throttle range is Rich or Lean, the second letter 'G', and the 3/4 throttle range is the 1st letter 'D'....

You can also set the Pilot & Main and then adjust the needle clip position from the 3rd clip to the 2nd to Lean out the 1/2 throttle range and vise versa before you go changing needles.

As an FYI....you can develop a good ear to jetting, and not need to perform Plug Chops for final tuning by just rding and listening to your engine, you should always jet on the Rich side, and with an OEM IGN gap your plugs on the low end, .018" to .022".

Carlos
 

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Thanks Carlos, that is a solid plan I will follow. One more question though.....the needle it came with only has three notches for the clip position, not five, like I am used to seeing. It is a DGH needle?
Jimbo:

The needle should be a DGH, and it should have 5 groves...have you removed the needle from the slide to inspect? If it has 3 groves and not 5, it is a defected needle from Sudco...please post a picture or email it to me at [email protected].

If the needle is defective, I will ship you a new one ASAP at N/C.

Carlos
 

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Discussion Starter #5 (Edited)
Jimbo:

The needle should be a DGH, and it should have 5 groves...have you removed the needle from the slide to inspect? If it has 3 groves and not 5, it is a defected needle from Sudco...please post a picture or email it to me at [email protected].

If the needle is defective, I will ship you a new one ASAP at N/C.

Carlos
Yes, I am 99.9% sure it has 3 grooves. I did take it out before installing to see where it was at for a baseline. I will pull it out tomorrow and send you a pic. Thanks!

Edit: It came with the correct DGH needle, I was wrong. OOPS!
 

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Yes, I am 99.9% sure it has 3 grooves. I did take it out before installing to see where it was at for a baseline. I will pull it out tomorrow and send you a pic. Thanks!
Yup...please send a pic or two, I am interested in the 3 vs 5 groves...would be the first time in a very long time I have seen this issue from Sudco/Kehein.

Carlos
 

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Discussion Starter #7 (Edited)
Yup...please send a pic or two, I am interested in the 3 vs 5 groves...would be the first time in a very long time I have seen this issue from Sudco/Kehein.

Carlos
I am headed to the garage now. I will put up some pics here in a bit, once I get it out. Thanks!
ETA: It came with the correct DGH needle, I was wrong. OOPS!
 

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Discussion Starter #9
Yup...please send a pic or two, I am interested in the 3 vs 5 groves...would be the first time in a very long time I have seen this issue from Sudco/Kehein.

Carlos
I am an idiot. It DOES have the 5 groove, DGH needle. Doh! I know what happened......a few weeks ago, I rebuilt the carb on my boy's 250EX the same night I got the PWK carb, and opened it up, seeing what jets it had in it, prior to putting it on the bike, weeks later, when I got my new carb boot. The rebuild kit for the 250EX had the goofy needle with 3 grooves instead of 5. I confused the one I put in the 250EX, for the one that was in the PWK. My sincere apologies Carlos, my memory isn't what it used to be. I will edit my earlier posts, to hopefully limit the confusion.
 

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NO big deal Jim...I am in the same Boat...as we get older or memory is not what it used to be. Glad to hear my eye site is not totally gone as well...again; don't sweat it.

Carlos
 

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Discussion Starter #11
So, I put the smaller #42 pilot in, and it is definitely better. I got the fastest idle at about 2 1/2 turns out (with further than that out, no different), so that even indicates I could go smaller on the pilot.....wow. While I was in there, I also bumped up the main jet a notch to a #162, to see if that would be rich on the top end (it ran pretty strong with #160). I also raised the clip on the DGH needle, to the 2nd notch, thinking the midrange was rich before.

Then I took it for a little rip in the lot next door. Idle circuit seems strong, full throttle seems good, no sputtering, maybe just a bit flatter on power than the #160, but not much of a change. What DID change, was mid throttle range......it went flat and lost power around mid throttle CONSTANTLY. Before, with the needle a step richer in the middle, it was noticeably flat in the mid throttle and boggy, but now, after leaning it out, it was way worse, and I had to go between full throttle and 1/8th throttle to even get home.

Could it be so lean on the needle to want to die out and lose power, with the DGH needle on the second from the top notch????? This seems strange to me, since the idle and main circuits seem to want lean settings for this motor. Next move, I will richen the needle clip in the 4th down notch, to see how that changes things. No time to fiddle with it further tonight. THanks for all the help guys.
 

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You gotta understand something,,, main jet is for WOT, not for motor hight rev,, i mean you could smash the gas to full open and only rev 5000 rpm, if it bog its still the main jet... not the needle....


having goog pilot, and good main jet, and you wont be touching the needle, its only for fine tuning...

40 isnt a lean jet for pilot neither is 55 rich, it all depend on ur motor vacuum and restriction... jet it rich and let the number alone !

start by the pilot jet, then jump on the main jet with full trottle pull and spark plug color THEN you can play with needle IF NEEDED and start over the pilot and main after...
 

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Discussion Starter #14
You gotta understand something,,, main jet is for WOT, not for motor hight rev,, i mean you could smash the gas to full open and only rev 5000 rpm, if it bog its still the main jet... not the needle....


having goog pilot, and good main jet, and you wont be touching the needle, its only for fine tuning...

40 isnt a lean jet for pilot neither is 55 rich, it all depend on ur motor vacuum and restriction... jet it rich and let the number alone !

start by the pilot jet, then jump on the main jet with full trottle pull and spark plug color THEN you can play with needle IF NEEDED and start over the pilot and main after...
Yeah, I understand all that. I am not an idiot. It runs awesome at WOT and idle. Its when the throttle is in the middle range, that is seems to lose power and feel like its gonna flame out. From what I have read, the middle throttle range is affected mostly by the needle. So, it would make sense that I need to adjust the needle. ANd since I leaned out the needle, and it made the mid throttle performance worse, it would suggest to me, to richen it, and see what happens. I don't know what part of my posts leads you to think I don't have the idle circuit and the main circuit close to spot on. My issue, is that, based on what I have read others to run, that with the DGH needle, It seems odd that with such lean settings on pilot and main circuits, the clip in the middle of the DGH needle seems reasonable. BUt, from what I have seen so far, I may need to run the needle way higher.
 

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if its that noticeable, you dont have the right needle for your motor... needle clip are mostly fine tune,,,, but give i a shot if it was funning fine in middle clip why not...
 

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What is your current setup? What is your location/elevation/temp? What you describe sounds like she's thirsty. Bog means lean sputter/smoke means rich. Mine likes a 45 pilot, a DEF needle on the 4th notch from top(rich) 172 main...had great success richening the diameter and going to the shorter (richer) needle.

Here is something else to check: Take your carb out of the boot and make sure when the throttle is closed the slide is all the way down also ensure it opens all the way when the throttle is fully opened...back out the plastic idle screw till it almost opens the slide. This process will make sure your cable adjustment isn't confusing your throttle position.
 

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Discussion Starter #17
Thanks Moneylover, yes, the throttle adjustment is good, and the idle is actual mechanical stopped by the screw and not the cable.
 

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Discussion Starter #18
Progress! I put the needle clip on the lowest (fifth) notch, as rich is the DGH needle would go, and took it for a short spin. It runs much better in the mid throttle range, no more bogging and flaming out, in the mid throttle range! It is totally rideable now, but It does feel just a bit flat arond mid throttle, most noticeable at about quarter throttle, so I'm thinking I could go even a bit richer on the needle. This sort of boggles my mind, since the pilot needs to be about a number 40 and only using a 162 main jet (which are very close to being perfect). My next plan is to shim up the DGH needle with some stainless number 4 washers, the distance of another clip position or two. That will tell me how rich I need to go to be too rich. And from there I guess try to figure out a better needle that I can run on the middle notch, so I have some adjustability. Once I get the needle dialed, I will do some plug chops to fine tune the main (but it runs strong now). Thanks for the continuing help guys!
 

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Discussion Starter #19
Update:

So I shimmed up the DGH needle with two washers, the distance of what would be a 6th notch, to richen it futher. I bogged a lot from a rich condition, from 1/4 to 3/4 throttle, and the 162 main even seemed to rich bog a bit with this setting.

So, knowing that the DGH needle had a slight lean bog in the middle position previously, and ran good, but a bit flat at the bottom 5th position, I tried the 4th position, which I hadn't tried before. Took it for a spin, and this seems to be the sweet spot! It ran like a raped ape, and the needle seemed about perfect there! Maybe the 1/8th to 3/8th throttle position seemed a touch lean, but the rest felt great! The 162 main was a bit rich but rideable.

So, I am getting there. If I could find a needle, that would be a touch richer in the 1/4 throttle area than the DGH, and the entire needle a notch shorter than the DGH, so I could run in the middle notch instead of the 4th notch, I think I would be dialed in! Any needle suggestions for this situation?

Thanks for all the help guys, this is exciting, to finally get this bike ready to ride!

Got my rear Hipers that came with it installed too!

 

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6 th clip = not the good needle... i would definatly look at keihim chart and order right needle OR check for good main jet !
 
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