Motors Motorcycle Mayhem

If it's an unknown time since any of them have been done, the basic service stuff is worth blasting through, especially the oil (be interesting to see what it looks like after what could be a very long time since the last oil change). But the fact that it was running rich before is your biggest clue.

Googling around, apparently the 125 version doesn't have manual choke or mixture adjustment, it's all fuel injection like mine (I've got the 250 version). If there's anything up with that I'll be no help as I haven't had a reason to tinker with it yet and it's my first fuel-injected bike. I'm not sure how you would service it without proprietary Honda kit, since it's ECU-controlled. Some of the guys in here will have serviced FI bikes with mixture woes though, maybe there are ways..

 

Actually, it's the 2004 model which is Carb'd.

All the standard servicing does seem like a good idea regardless though.

 

Well, I was getting similar problems on my first CG because I got the choke on/off positions mixed up and so did the mechanic I took it to. Much time was wasted. Barring that, it sounds like the mix is wrong. There's the manual adjustment nut on the carb (which I mistakenly ****ed around with before realising what was going on) but if it was okay before, you shouldn't need to adjust it.

Unless the previous owner fiddled with it, of course...

 

Out of interest, which way is the choke on/off. It's well and truly possible I've got the same issue. I'm assuming you pull it up to engage the choke, and it should be down normally.

 

Yes, that's the way round it was on the CG. I had the opposite intuition and thought that pushing it down would turn it on! However, I wouldn't swear that it's the same on both bikes, so best check the manual. (I unfortunately didn't have the manual with my first CG.)

The other so-obvious-it-gets-overlooked factor is if the fuel is really old, but if you were riding it before putting it into storage three months ago that doesn't seem likely unless it was really light use before then and it hasn't been emptied and refilled in much longer. I know for a fact that three months isn't long enough for petrol to denature, I've left mine standing that long before.

 

Three months?

Drain your carb. Errr the "float chamber"? It should have a screw to drain it, then let fresh fuel in.

A constant problem on my old Honda, the fuel in the carb would gas out over the breathers if I let it stand for over a week.

My Ducati does the same, but only when left standing for over ~two months.

Simple solution is to close the fuel line about half a kilometer from your house.

 

Sounds like a plan. Alas I go back to uni on friday and I'm not taking the bike with me.
Hadn't planned on riding it over the christmas holidays anyway, but at this rate I don't know if I'm going to get much chance over easter either.

 

Had to get my bike picked up by my mechanic. Wouldn't start after a month standing over winter. All charged up and everything in order but refused to fire... Sad times...!

 

This sunday I got stuck with a flat battery and had to beg a jump start AGAIN, this has now happened about 5 times (the first two I bump started it, unwisely - being fuel injected it seems to hate this because the ECU can't do its little calibration routine, and it rode terribly and probably could've seriously messed up the engine).

The problem is my heated handgrips, installed by the first owner, are wired straight into the battery, not into a part of the ignition circuit. So if I forget to turn them off on the dash, they drain it flat.

Choice: do I try to wire it in myself (I'm handy with shrink tubing and electrical tape, but I've no idea how to read the wiring diagram in the manual, or how to locate the relevant wires in the mass of identical black wires under the seat) or do I take it to a garage to get them to do it, spending an arm and a leg on labour time?

 

I'm a bit of an electronics geek so I might be a bit biased, bit it sounds like the easiest job in the world to do (apart from pulling everything apart obv, although if your cbr is anything like my cbr that shoudl be fairly easy). Just go and watch a few videos on youtube on how to solder properly; if you're lucky there may even be a proper vid on how to install the heated handgrips properly.

Personally I would have a look at wiring it up to the headlight circuit if you just want a quick hack, although I'd wait for a second opinion on that one tbh.

 

Swapped my fuel pump over so hopefully this is the end of my fueling/running rich/black spark plugs/poor economy woes...! Just a dyno run to confirm!

 

I hear a lot of seasoned bikers talking about fuel pumps in the context of replacing or troubleshooting them, but I've never had any problem with one to even alert me to its existence - is it a part that only exists (or only causes problems) on bigger bikes?

[/inexcusable mechanical ignorance]

 

So yeah, my bike has been playing up recently, it takes 10 minutes to start. Turns over lovely but doesn't fire up. I charged the battery, changed the plug checked all the connections.I put it down to cold weather but this evening I managed pull my key out of the ignition barrel whilst the bike was on (but not running) so I guess I've found the problem. It seems to turn over if I force the key in and hold it while I turn it over.

Ignition barrel easy to change? >.<

I've got a 2012 YBR 125.

 

I don't think it's a common fault BE, just one with my bike! The problems I'm having can be seen in the graph below. I'm going to adjust the TPS this week and I've a friend looking around for the kit needed to sync the throttle bodies and then I'll go from there. (Green run is a newer SV for comparison. It still runs rich but is better. Similar curves though.)



EDIT: And you're not ignorant! I'm discovering a lot of this along the way. Love getting mucky working on a bike so enjoying it quite a lot. Well, aside from the substantial (for a student!) monetary costs!

 

Does it have a steering lock integrated into the ignition barrel? Does it have any electronic security, immobilizer or anything?

My CBR 250R's ignition barrel had to be replaced after a theft and recovery and it was the most difficult part to obtain and fit, so the garage told me, because it's integral to the bike's electonics, ECU, etc. and has to be 'set up right'. They didn't specify what that really means, but I infer it was beyond what I could've done myself.

If yours hasn't got any of that fancy stuff it's a nuts and bolts job to replace the barrel, but I see from MCN that the YBR 125 is at least fuel injected, which smacks of over-fancification for a 125...

 

No fancy stuff, just a steering lock!

Its a bit redundant now, i crashed it this morning! Aha...

So its being picked up tomorrow to be straightened out : P

 

In the world of legendary engines, Honda's V-twin from the Transalp/Africa-Twin/NTV/Revere/Deauville (and I've probably forgotten some) is considered bombproof, but it has a persistent niggle with the fuelpump.
Not the pump itself dies, but the pumprelais that is built into the pump in these types tends to die (burn it's contacts).

But no, I don't think fuelpumps are a big problem in general.

Don't think there are any new bikes with carbs anymore due to emissions laws...
Effin 50ccs are fuel-injected now.

 

Ugh, really?

I retrospectively love my CG even more. Simplest machine imaginable, if only it had been a bit more powerful.

 

Well, the early fuel injections were easy and actually simpler than the last carburators.
I suppose the ones for the small bikes still are.
You just need three sensors and you're done. (MAP, Temp and crankshaftposition* really)
Carbs on an engine with catalytic converters can be very complex.

*or something similar

 

Yeah I just have a sour attitude towards fuel injection and ECUs since having a period when my battery was always flat (heated grips wired wrong) and it was effectively impossible to jumpstart because, even if you got it going, without the ECU doing its ghey little pre-flight checks the bike couldn't run properly and would just stall within a minute or two. The CG was so basic, so close to lawnmower tech, that I often bump started it and thought nothing of it - it was almost as easy as kick-starting, and the bike didn't care.

In other news, I came by the bike today and found that the radiator fan was going - with the ignition off. Had to disconnect the battery. Googling revealed that it's a non-switched circuit, so it is always on; my uncle speculated that it must be a faulty temperature sensor. Anyone had any experience of this kind of problem before?