XR650R Carb on a XR650L



258 replies to this topic
  • HBLARRY

Posted March 04, 2009 - 10:35 AM


Do these jets make me look fat?

Ok I got this thing installed and running 68s pilot, 165 main, b53e(hop up needle) 4th position, stock internals on the engine, uni filter and a supper-trap isd2 8 discs.

I am getting poping at 3/4+ throttle, rough idle +/-150 rpm, smooths out around 2000 rpm. Fired right up and warmed up fast, no choke needed, when I open the choke RPM picks right up and it smooths out, fuel screw didn't seem to doing anything. What do you think?

Thanks


pxdthumper,
I would have to agree with Kenzo on this one..........the 68s is a richer pilot and you've described a too rich condition @ idle. Make sure you are not set too high on the idle speed and picking up fuel from the needle along with the pilot. I doub't if you could get the idle mixture screw to compensate for that.
Lower that idle speed way down and allow the engine to draw only from the pilot and adjust it ( 1 1/2 - 2 turns +/-). Then...... if you feel you need to raise the idle speed do so by raising the slide up slightly (thumb screw) from the fully closed position.

All this above is going to amount to a hill of beans if you have an air leak between the carb and the manifold. Be absolutely sure it is sealed air tight and the choke is fully open ( I hope you didn't have the choke full on and the idle way up).

Since it's been determined that the 165 main is close to optimum for this engine, putting in an even richer needle and then raising it up on the clip position to make it even richer yet is going to play havoc on the 1/4 to 3/4 operation. Lower the needle by moving the clip toward the top of the needle in the #1 or #2 position..........start off leaner then progress in small increments richer.

The way I understand this (assuming the ignition timing is correct).......... that if you are back firing through the exhaust you are igniting unburned fuel in the header pipe from the flame front from the combustion stroke when the exhaust vale opens. Definitely too rich. Makes you wonder about the wall strength of a sheet metal pipe or muffler vs. a cylinder sleeve.

Too bad we can't get a convincing video sound bite from one of these fire breathing beasts revving up..........Anyone want to volunteer ???


HBLARRY

  • Kenzo

Posted March 04, 2009 - 11:28 AM


Come on Kenzo, I'm counting on ya before I install my 68 pilot. :p

I've got the 65 now with a 165 main and I forget which needle in the middle groove with shim. It pops on decel, but otherwise runs really well. I've been debating about trying the #68 to cure that pop.:moon:


maybe u shud also confirm the ACV is operational...if it's been disabled u'll need a fatter pilot to prevent backfiring...

i'm gunna try to install the 68s and HRC needle tomorrow (Thursday) going riding today and don't want to chance it not running gud for the :moon:

:ride:

  • pdxthumper

Posted March 04, 2009 - 12:07 PM


Thanks guys, I agree that I am too rich, I knew going in that, that would be my risk. I will pick up a 65 pilot, and lower the needle. The choke is off and it will idle, just not smoothly. The ACV has not been modified. I'll check the boot fitment as well to rule out air leaks.
Even running poorly the throtle response is surprising :p

  • Kawidad

Posted March 06, 2009 - 09:06 AM


maybe u shud also confirm the ACV is operational...if it's been disabled u'll need a fatter pilot to prevent backfiring...


Seems to be operational. All of the parts are there. :p

  • SHARPMACHINE

Posted March 06, 2009 - 10:19 AM


Pretty cool thread, reminds me of people running trx450r carbs on trx400,s and xr400's

  • pdxthumper

Posted March 07, 2009 - 01:40 PM


Ok I changed out the 68S an put in a 65 piot, same 165 main, and lowered the b53e needle to the 2 clip position, fuel screw at 1 1/2 turns out. Starts and runs great through out the throttle range, minor pop on decel. Certainly a bump up from Daves carb mods, though more money but still not bad. Thanks to the group at large for the help on this.
Cheers!

  • Kenzo

Posted March 07, 2009 - 03:45 PM


Ok I changed out the 68S an put in a 65 piot, same 165 main, and lowered the b53e needle to the 2 clip position, fuel screw at 1 1/2 turns out. Starts and runs great through out the throttle range, minor pop on decel. Certainly a bump up from Daves carb mods, though more money but still not bad. Thanks to the group at large for the help on this.
Cheers!


try it 2 1/2 turns out...:p

be warned if u have a FMF header there is probably a small leak where the pipes join...it's the burble on chopped throttle feature that they don't advertise :moon:


:ride:

P.S. ...have u done any roll-on roll-off testing for that 165? ...still debating bumping my 160 :moon:

  • Kawidad

Posted March 08, 2009 - 07:26 AM


I have the 165 in mine and it runs real good at WOT. I ride several long rode stretches to get to the trails where I run it at near WOT and it runs well and seems right. Way better than the original CV with Dave's mods done.

  • Kawidad

Posted March 10, 2009 - 07:51 PM


Okay I put the 68S pilot jet in and it runs like crap. Waaaaay too rich. I'm definitely going back to the 65.

  • Kenzo

Posted March 11, 2009 - 05:12 AM


Okay I put the 68S pilot jet in and it runs like crap. Waaaaay too rich. I'm definitely going back to the 65.


...so exactly how did it react to the 68s??? :)


:banghead:

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  • Kawidad

Posted March 11, 2009 - 06:55 AM


...so exactly how did it react to the 68s??? :)


:foul:


Very hard to start. :p Once started, it idled fine, but then when you whacked the throttle, it blew MAJOR amounts of black smoke until it cleared itself :banghead: and then was a decent color at WOT. In that RPM range where it was blowing the black smoke, it burbled. No question it was too rich. :banghead:

  • pdxthumper

Posted March 11, 2009 - 08:16 AM


Ok thats two strikes against the 68 with 165 main. So it looks like people are running with the 65 pilot, and 160-165 main?

Are you guys disabling the ACV?
How about the choke plate mod?

  • Kenzo

Posted March 11, 2009 - 11:09 AM


Very hard to start. :p Once started, it idled fine, but then when you whacked the throttle, it blew MAJOR amounts of black smoke until it cleared itself :) and then was a decent color at WOT. In that RPM range where it was blowing the black smoke, it burbled. No question it was too rich. :banghead:


hummm...i still may try the 68s since mine needs just a little more fuel beyond wut the fuel screw can provide(max'd out)...w/ the 68s i wud expect no choke required for starting unless VERY cold ambient conditions...

w/ the 65/160 i have to bump up the idle screw one turn and slightly crack the throttle for cold starts...again i think a fatter pilot wud help.

Ok thats two strikes against the 68 with 165 main. So it looks like people are running with the 65 pilot, and 160-165 main?

Are you guys disabling the ACV?
How about the choke plate mod?


currently stock 65 pilot (tests correct), 160 main (tests correct), choke flapper removed and ACV intact...runs pretty damn gud but look'n for sumthing extra :foul:

if i disabled the ACV i wud definately need the bigger pilot.

:banghead:

  • pdxthumper

Posted March 12, 2009 - 11:03 AM


I mounted a perch switch from highway dirt bikes to replace the starter / kill switch button. With the R throttle and cable routed on top of the bars, this really cleans up the control area. In addition to the switch, you need to wire in a relay to turn off the headlight when your running the starter.
Posted Image

  • Nummie

Posted March 13, 2009 - 05:01 AM


I mounted a perch switch from highway dirt bikes to replace the starter / kill switch button. With the R throttle and cable routed on top of the bars, this really cleans up the control area. In addition to the switch, you need to wire in a relay to turn off the headlight when your running the starter.


Looks great, but I'm missing something here (sorry, I'm a little slow). Is that red button the kill or starter?

  • Kenzo

Posted March 13, 2009 - 05:42 AM


I mounted a perch switch from highway dirt bikes to replace the starter / kill switch button. With the R throttle and cable routed on top of the bars, this really cleans up the control area. In addition to the switch, you need to wire in a relay to turn off the headlight when your running the starter.
Posted Image


Looks great, but I'm missing something here (sorry, I'm a little slow). Is that red button the kill or starter?


that does "clean" things up... :)

...maybe the dual switch with one for the starter and one for the kill switch???

...and why doesn't the stock starter relay which kills the lights when depressed work with this switch??? :banghead:

TIA,

:banghead:

  • pdxthumper

Posted March 13, 2009 - 08:20 AM


Thats the starter button, I removed the kill switch I never used it, I still have the stock key, and the only time I ever touched it was when the bike wouldn't start, because it had been switched inadvertantly.

The stock starter button switches the headlight voltage supply to the starter relay, this tuns off the headlight when the starter is running, and powers the headlight otherwise.

The single and dual switches are the price, and I almost bought the dual just because, But origanally I had the throttle cables under the handlebar similar to the stock "L", but the button just barely fit and I think was rubbing on the throttle cables. So I don't know that you could really use both swiches.

  • HBLARRY

Posted March 13, 2009 - 01:50 PM


PDXTHUMPER,

That's a nice clean look for the throttle side.
I personally like the idea of a kill switch on the left side without taking my hand off the bars to reach around for that buried key.

Baja Designs makes a nice dual sport turn signal (push to cancel), lights, horn and kill switch for the left side that "Might" be adaptable to the stock "L" ??? The wiring just might keep you busy for awhile. The connections are in the tech section of their website.

Posted Image

HBLARRY

  • Kenzo

Posted March 13, 2009 - 03:34 PM


The stock starter button switches the headlight voltage supply to the starter relay, this tuns off the headlight when the starter is running, and powers the headlight otherwise.


sounds like u need a "momentary double pole single throw switch" with one normally open the other normally closed :)

PDXTHUMPER,

Baja Designs makes a nice dual sport turn signal (push to cancel), lights, horn and kill switch for the left side that "Might" be adaptable to the stock "L" ??? The wiring just might keep you busy for awhile. The connections are in the tech section of their website.

Posted Image

HBLARRY


i installed one of these for a bud...it has the nice feature of being able to turn off the headlight, killswitch and highbeam indicator...the downside is the quality is not even close to the stock Honda stuff :banghead:

:banghead:

  • D0T-C0M

Posted April 17, 2009 - 05:27 PM


so if u decide to do this carb swap u can ether use the R's throttle and cables as-is...or use the L's cables and cut the protective sleaves to expose more cable to match the carbs requirements.


Would it be possible to modify the carb bracket that the throttle cables are connected to instead of cutting into the XRL cables? I was thinking instead of modding the stock XRL cables you could mod the bracket to bring the cables closer to the throttle assembly. I haven't received my XRR carb yet so this was just a thought but in the pic below it would seem like it could be possible.
Posted Image

i'm gunna try to install the 68s and HRC needle tomorrow (Thursday) going riding today and don't want to chance it not running gud for the :p


Did you ever try the HRC needle? The carb I bought off ebay has the HRC jets installed already. I would be curious to hear if you had a chance to test this?





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