310R popping & hard start

hi Daniel-

Just to be clear, you believe it was a new injector that solved your problem... and not the 3 (?) sensors you replaced? correct?

did you at anytime try cleaning the injector or did you just decide to get a new one?

thanks.

I replaced the water temp sensor first. Made an improvement but still had a bit of popping and hunting idle when hot. I then changed the air temp sensor.. no change. Then did the map sensor and still no change. Finally I tried to get the injector cleaned but the places i tried were going to charge more than a new injector to clean it. I can't say if cleaning would have solved the issue or not.

If cleaning was cheaper than I would have done that first.

Update:
Put in new CTS, covered most of under / inner /front sides of fuel tank with heat shield. Went for ride at 65F temp , about 4000 ft elevation. After full warm up , bike continues to pop on decel, and will often die after short time idling (15 - 30 sec.) Reluctant to start when at operating temp. In short, no improvement , maybe worse. Inside of exhaust exit is sooty black. Looks rich.

After reading above post, an injector cleaning may be next. But is seems odd that clogged injectors would cause the rich sooty exhaust.

I'm getting kinda old so I CRS.... but it seems to me that a light, dry, fluffy soot in the exhaust was caused by a rich fuel mixture. Now if an injector is clogged, there might be droplets of fuel not getting atomized. So it'd run lean, but the muffler would show rich. That's a shitload of speculation on my part, I know. Let me go a bit farther: it seems to me that if the fuel pressure is low, you'd get the same kind of problems too.

If you do take the injector out- take a good look at it before doing anything, then try a spray pattern- so now you've established a baseline. Then clean it and see if things change. A simple blast or two of carb cleaner may do the trick. This would also be an opportune time to get a pressure gauge on the fuel line.

keep your old CTS- they're a known-associate of weird-ass problems.

hey MZ- I've been meaning to ask: does your bike start any better if you pull the cold start (when hot)? Also, I'm not sure your problem is caused by elevation... I'm thinking it just gets worse in thin air. Is that your opinion too?

good luck.

I have the injector out. It appears to be spraying and atomizing well a(need a close up slow mo video) .When sprayed onto cardboard, it looks quite like a small spray paint blast - but of gas.
Will get carb cleaner to run thru it, and hopefully a fitting and pressure gage.

I am beginning to think it is just injecting too rich. The popping and starting issues happen after engine reaches full operating temp. Hotter is worse. When cold, I never have to use the cold start knob. If I use it , it cranks longer before starting. Few times I tried it for hot (reluctant) starts, knob use did not help. Next thing may be Power Commander V.

cleaning: you can and should do the "full-on" carb cleaner sprayed thru the pressurized injector method; but OTOH just spraying with cleaner where you can may help too. btw, 12 holes in the injector IIRC? ...should be 12 streams then... or 4 and 4. whatever. I dunno if these injectors have the little filter thingy in 'em... but look.

video: that'd be great for the injector; but hell- do it for everything: let us see & hear your exhaust & erratic idle, let us hear the popping at altitude, let us hear the more normal running at 2700' and finally- take the newish spark plug out and let us look at that too.

I'd like you to rev the hell out of the bike also: bounce off the rev limiter in all 6 gears on a flat road. it should come close to scaring you- mine will lift the wheel with every shift.

IIRC, we're looking for about 43psi/3.5bar on the fuel pressure- the test rig doesn't hafta be anything too special.

good luck.

I read some other threads re. injection issues. One point made was the need for good battery voltage. My battery ( the original ) has been getting weak. 13v no load. Press starter (click - will not turn engine) V goes down to 3v. Might this be the cause of the problems? Another possibility: My bike still has the spark arrest screen in muffler tip, and the backfire screen between the air filter and air boot. Are these restrictive enough to choke a bike?

Keep both screens ( I run both) and yes a weak battery will and can degrade starting. It just seemed like my EarthX provides steady strong power even bumping up against the decompressor where the Yuasa would not have the power to get by it and would be flaky when hot. 13v seems ok but not sure if checking while starting is telling. See while running where it is (13+-14) and if you check it the next day if it's down to 10-11.Otherwise it may be ok. If the bike clicks, I get off it right away and next push usually get's right by TDC and spins up.

Is your velocity stack opened up. That and the TE air filter cage were the main blockages. A fully open pipe may be the optimum for Map 3 though and be what is is designed for. I did the PCV and Autotune since I was bugged with what you are dealing with though primarily above 6500ft to 14k. Once installed it made a substantial difference at sea level too. Bike has been a complete non issue for at least 2 years since then. Mp Switch, PCV and Autotune. If you can't get it 100 percent the PCV will allow you to tune it period. I have 2 maps others used with success so you would be able to get by w/o Autotune and welding an 18mm bung to your header.

Hey MZee-

Bring your bike to the NW gathering (first weekend in November), there will be a lot of folks there they could diagnose your bike (including BillF who has/had a 310).

I'm thinking of showing up; so is my kid (in Portland)- we're camping at a motel in Bend. c'mon out.

An update: Removed injector & kicked engine over. I see a nice misty spray & a wet spot if sprayed onto cardboard. Without closeup hi speed video, cannot give any more detail. Removed injector & squirt in some carb cleaner, hook up injector & kick starter to run cleaner thru. I see same (good?) spray pattern. Fumbled around on internet & locally, trying to fine correct fitting to do pressure test. Dont find. Re- assemble bike. Start up & do Volt test on battery - get 11V at idle to approx 3000 - 3500 rpm , then it jumps to 13.5v.
Install new battery. Measure 13.5v.
Go for a ride, after too long since last one. Bike runs well, usually starts easy, little or no popping on decel. The occasional reluctant starting and popping seem to happen after a climb - hotter engine.
I think the recent problem of a lot of popping & hard starting was due to a tired battery - low Voltage at low RPM messing with the injection system. It still has the lumpy hot rod car idle.
My next fix may be a Power Commander.

Thanks for the invite.

if you are measuring 13.5v running, with a new battery (after giving it a chance to charge) you have a charging system problem.

Trenchcoat 85: I just discovered your reply today. I measured (about) 13.5v right after installing new battery, first startup. What should it read, idling, and revved, after running / charging?

14.3v or somewhere in that neighborhood (IOW: 14.0-14.5v with a nominal load)

Hey MZ- any progress or new to report?? it's been 7 months now; hoped you solved it.

No. Still working on it. This spring I installed a JD tuner. It helped the erratic idle issue - until the bike reaches full operating temp. Then still has the hunting idle speed. Idles best with tuner on richest setting for idle. Still is reluctant to start when at operating temp. Next effort will be to set TPS. Just received TPS electrical connector for setting voltage. I now need to search forums to learn correct TPS setting. Will report results.

measure your TPS voltage currently before adjusting.

I believe 680mV is the setting for a closed throttle.

Describe your problem again, as completely as you can. IIRC, your symptoms started as a lean bike thing, and kinda morphed into a "rich" problem.

also, read this thread:
http://www.cafehusky.com/threads/2013-txc-250-starts-cold-stalls-hot-then-wont-start.86961/

A much delayed report: Too little riding done in what was a way too hot summer here.

I set the TPS to 680 mV. Rode and fiddled with JD tuner settings. Realized that I was confused about the JD color codes for idle and low RPM. I had idle too lean and low rpm too rich. After trying different settings, Set Idle to 7, and low rpm to 6. Also added some accelerator pump function. For the first time in the life of the bike, it will idle smoothly without missing and hunting.
Since resetting, I have not yet tried had it on a tight trail, but I believe the low rpm stall is gone. It still does the popping on decel with throttle off. Still some times reluctant to e-start hot (will crank, but not fire), but will fire up with a quick foot start. Should have replaced battery with new modern battery instead of another lead batt. Progress made, rideability improved. Better batt may fix start issue.

Here we go again. After first few rides on the season, I see that the problems persist, but are worse: After warm up to operating temp, the bike will not idle more than a few seconds. Tight single track riding is not fun, as the issues are worse in low rpm / low throttle running. It wants to die often when the throttle is closed. Runs great with throttle opened more than 1/8.

Have checked TPS, set to .68v. Resistance across TPS is 700 ohm closed, 1400 ohm at open.
Checked resistance across injector connection pins: 9 ohm. Do not know correct resistance & do not fine the number in WSM.
Checked coil resistance: About 0.1 ohm across pins. My meter scale does not go down to deci ohm. Reads to spec - 5700 ohm on secondary. Do these coils tend to go bad when hot?
I have read other threads re. similar problems & symptoms which were fixed with new coil or injector.
My first choice to replace would be injector. I'm open to suggestions & info. Thanks