YBR starting issues

[steve.s.scott]

First off, hello all and I would like to congratulate myself on my first post .

Now, I purchased myself a 56 plate YBR with 12k on the clock a week ago. It ran fine for a few days then one morning it wouldn't start. The electric start died after two attempts and it wouldn't start on the kick.

I charged the battery and the same happened again, so I sourced a new battery. I charged the new battery to full, and tried again. The bike turns over fine but doesn't start, either on the elecetric or the kick.

I have checked the spark plug, and it looks ok, but I have ordered a replacement just in case, but if this doesn't work I am stuck! (How can you tell if a plug is 'spraking' anyway?)

The bike has a quarter of a tank of fuel and enough oil, I have tried starting it on both the reserve and normal and checked the wiring for any obvious corrosion, which seems ok.

I checked the MOT and it appears the bike has only done 20 or so miles since December, so I guess it has been sat about all winter and hence the dead battery. Would it be worth draining the fuel and oil and changing it? (Although it started fine a few days ago so I assumed it wasn't this..)

Any advice would be much appreciated, otherwise I guess it's time to take it to a garage .

Cheers

Steve (the YBR Rookie)

[Robby]

To check if the bike is sparking, hold it close to the engine whilst plugged into the HT lead and kick it over or thumb the starter. It will spark against the block. I normally touch it onto the head and see a spark.
There is a chance of getting an electric shock here, but I've never got one. Wearing latex gloves probably helps. You're looking for a strong blue spark.

If it has sat over winter with a mostly empty fuel tank and then only been run a few times, there is a fair chance that condensation (water) in the fuel tank has worked its way down to the carb, which will stop it from starting. To fix this, hold a cup under the drain point on the carb (may be a thin rubber tube leading down to somewhere near the back wheel) and open the drain screw on the bottom of the carb. Do this with the fuel tap set to off. The stuff that drains into the cup may be a mixture of petrol and water. Water is obvious because it doesn't mix with the petrol, and will probably be a bit dirty and rusty - rusty crap dissolves into water more readily than into petrol.

Those are the easy checks to make it start. Make sure to turn the fuel back on before you try to start it again. If there is water in the fuel, then don't be surprised if this happens again. Fuel tanks tend to have the fuel tap slightly above the lowest point, so water will sit at the lowest point and stay in there when you drain the tank. The only sure fire way I know to fix this is to drain the tank as much as possible, then leave it in a warm dry place until it is totally bone dry. An airing cupboard is suitable, or in front of a fan heater for a while.

Avoid the temptation to play fuel tank ramjet. It does make a cool noise, but you will bubble the paint and you will burn your fingers.

[temeluchus]

You can hold the spark plug against the engine with it in the HT cap, and turn it over to check the spark.

Drain the float bowl and turn it over a few times with the fuel tap off to help clear it out. Then turn the tap on and try again.

Another trick is to warm the sparkplug up in an oven, refit and try.
____________________
Some shite cruiser. Now with guns and FREEDOM!

[steve.s.scott]

Cheers guys, will give it a try .

At the very least I can eliminate the spark plug and water residue. (Although all I have is the small service manual that comes with the bike, and from what I can see only references the oil drainage valve, but I am sure with some tinkering I will be able to drain the fuel.)

Any reason for setting the fuel tank to off?

Avoid the temptation to play fuel tank ramjet. It does make a cool noise, but you will bubble the paint and you will burn your fingers. I have no idea what this means, but I must admit, I am tempted...

Who knew bikes would cause such problems

Steve

[Robby]

[nelly18]

I was having the same probs with my 56 plate YBR. On the advice of mechanic I've had the ignition barrel replaced. Now it's blowing fuses!! grrrrrr! I've given up now. Can't afford to take it back to garage. Won't be sitting my test anytime soon. Bummer!

[herulach]

Can't help with your issues, but hit up this link and read the second to last post for links to the service manual & parts catalogue.

https://www.bikechatforums.com/viewtopic.php?t=196868&highlight=

[neil.]

I would also check the fuel filters - both of them; the metal strainer in the tank itself and the plastic one that sits in the fuel tap assembly. Might be clogged with crud if the bike has been sitting for a while. Or it might be a clogged up fuel cap which is stopping petrol leaving the tank properly. Also could be a blocked air filter, worth checking the breather nipple and opening the filter up to see if it's full of rubbish. Failing that, maybe an ignition problem - coil or CDI unit. It's a process of elimination - do the things which cost nothing first! Good luck!
____________________
CBT February 2008 | A2 June 2008 | Yamaha YBR125 (written off) | Honda CBF125 (current)

[steve.s.scott]

[.]

Your bike probably has a carbon and fibre HT lead inner to conduct the spark from the coil to the plug.
This can break down after several years and will prevent any spark from actually reaching the plug.
If this is the case then A new bit of copper core HT lead will cost about £1 and hopefully solve the problem.

Normally the standard lead just unscrews out from the coil.

[steve.s.scott]

Just in case anyone is interested.

I got a mobile bike mechanic round to have a look at the bike and he got it up and running in about 10 minutes

It turned out the Tappet (SP?) bolts were too tight to the engine wasn't getting any fuel and so wouldn't start. (The spark plug I put in was fine in the end and was sparking away like a little beauty).

Needless to say I am stoked and been flying around on my bike since!

Anyway, just to say cheers for the responses I got.

Steve

[cb1rocket]

tappet bolts, sounds more like related to the valves but then you mentioned it wasn't getting any fuel.

I'm confused, can you enlighten us?