Idle not "settling," return cable too tight?

[psychocandy]

When I give the bike a rev, the throttle has good snap-back, but the idle doesn't seem to quite settle where it should.

I did the R6 throttle tube mod/upgrade. There IS slack in the throttle return cable, but is this still possibly indicative of still not enough slack in the return cable?

The idle returns to where it should be usually after a few seconds or after feathering the clutch a tad and putting a little bit of load on the engine (as you can hear me do around 0:12 in the vid below).

 

 

 

[74jimbo]

mine does the same at stop lights.....

I have heard that you have to be very meticulous as to how the cables are routed -- but not sure if his is the issue

[Matje]

Known issue; search for "hanging idle".

See for example here:

I never found a definitive solution

Edited September 14, 2017 by Matje

[HansLanda]

I had a similar hanging idle with my FCR. More accurate jetting solved it. I was running rich.
Also my throttle cables at one point would rev the bike if they were on the wrong side of the steering lock, and my bars were turned left. I rerouted them behind the headlight better so they had more slack.

[ohiodrz400sm]

Looks/sounds like a tuning issue to me.
Did you physically look at the throttle wheel on the carb to see if it was returning slowly the final few millimeters? That would be a good place to start.

[HansLanda]

Also, did you shave the excess off the R6 throttle? It will can very easily get stuck open if you don't cut it or install it wrong.

[psychocandy]

9 hours ago, ohiodrz400sm said:

Looks/sounds like a tuning issue to me.
Did you physically look at the throttle wheel on the carb to see if it was returning slowly the final few millimeters? That would be a good place to start.

Looking at the butterfly on the carb side, it all looks good. I'll try giving it a little more slack. I gave it some after I took the vid, but since the engine was hot, I could only do so much.

[psychocandy]

8 hours ago, HansLanda said:

Also, did you shave the excess off the R6 throttle? It will can very easily get stuck open if you don't cut it or install it wrong.

I did not trim the throttle tube. There seemed to be a lot of conflicting info as to whether that was necessary. What do you need to trim? Not the throttle stops bc the carb stops before the throttle stops even matter.

[ohiodrz400sm]

What other mods? Jet kit? Exhaust? Have you used starting fluid to check for an air leak?

[psychocandy]

Bike is new to me. It has a slip-on, not a full exhaust. I don't recall this happening with the stock throttle tube. But I've spent more time getting this bike set up than actually riding it.

[ohiodrz400sm]

Check for an air leak. If it has the 3*3 and slip on it needs to be rejetted if it hasn't already.

[psychocandy]

5 minutes ago, ohiodrz400sm said:

Check for an air leak. If it has the 3*3 and slip on it needs to be rejetted if it hasn't already.

Slip-on but no 3x3. Slip-ons generally don't require a rejet.

[ohiodrz400sm]

This bike is boarder line too lean from the factory. I'm not convinced that's your sole problem but it's certainly not doing it any good.

A DRZ with a slip on, 3x3 and properly jetting run noticable better than a stocker.

[mtnpat]

What ohiodrz400sm said.....hanging idle is usually the symptom of jetting being too lean (and every Japanese bike I have ever owned came jetted too lean). 

[psychocandy]

Gave the return cable a li'l more slack and it mostly solved the problem. Now the idle hang up is for just a second & goes back down without having to put a tiny amount of load on the engine.

Still don't think slip-ons require a rejet. But 3x3 is on my to do list. So, no matter what, there is a rejet in the bike's future eventually. I'm at sea level & bike will be at sea level for 99.9% of its like probably. Is there a easy peasy jet kit for 3x3 I can get? Or do most people do a li'l trial & error?

[ptgarcia]

You may not need to rejet when adding a slip on to an already well tuned bike, but even stock the DRZ could use some tuning. Mine had a terrible mid-throttle surge when stock.

[psychocandy]

Hmmm, it doesn't appear to be the throttle mod. Nor does it appear to be the nipple that I used to cap the emissions vent thingy.

Upon further inspection, it appears to not be an issue until the bike starts to get hot - not like overheating hot, just like riding for more than 1/2 hour hot. Once the bike is nice & hot, putting a little load on the engine by slipping the clutch a bit will bring the idle back down to normal.

Any ideas?

Edited September 20, 2017 by psychocandy

[ptgarcia]

Probably a bit rich on the jetting.

[Backwoods-Bomber]

Again, do the 3x3 and re-jet with a James Dean jet kit. These bikes are very lean in stock form.

[psychocandy]

Yeah, i was gonna see if I could just get the tune right on the stock settings. But I probably have to pull the carb to drill out the plug to access the fuel/air screw. So, at that point, I might as well do the JD Jet Kit. OK, you're all right.

I'll order the jet kit, just a quick question though. I've got a pretty much brand new No-Toil air filter in there. Does the 3x3 & JD kits require a high flow filter like a K&N or can I keep using the No-Toil at least until the next time I change the air filter?