HELP, Engine Problem

[rodrigoscs]

Hi All,
I have a Derbi Terra 125 that has been on the shed for quite a while. I got it out now for a full service prior to sell it, although I'm finding a very strange problem that didn't happen when I stored it. Bike starts on the button, sounds OK, has new air filters, new fluids all over, new fuel, battery, spark plugs, etc. Although, when I put it in gear it cuts off. I checked the side stand switch and it's fine. Another strange thing is that it rolls when in gear, offering very little resistance even in 1st gear. I tried to start it in 1st gear, without clutch in and the rear wheel starts rolling for a few seconds and then cuts off, although it pulls but it's not strong. I suspect the clutch plates might be stuck, even though the bike was stored with oil.
Any suggestions would be appreciated.
Thanks

[rodrigoscs]

Could it be also a compression issue?

[daryl]

Could it be also a compression issue?

Chuck a little oil in the spark plug hole and try starting it again. It'll smoke a bit until the oil burns off but should be a good indicator of whether it's a compression issue or not.

[Brenhden]

Could it be also a compression issue?

Chuck a little oil in the spark plug hole and try starting it again. It'll smoke a bit until the oil burns off but should be a good indicator of whether it's a compression issue or not.

Please forgive my ignorance but what are the possible outcomes of this test and what do they mean?

[daryl]

Please forgive my ignorance but what are the possible outcomes of this test and what do they mean?

If the compression is low due to the rings sticking, then the oil should seal it up a bit and let it run properly (or at least better) until it burns off. No difference in how it runs would indicate that it's not the rings causing low compression (that or they're totally buggered)

I've also had it where whatever was causing the low compression went away after it ran properly for a short while (enabled by the oil).

I'm not a mechanic by any stretch of the imagination, just throwing ideas out based on what's worked for me in the past.

Another thing I've seen that sounds similar to the original problem was caused by a cracked plug causing weak running (admittedly that was on a lawnmower) Just re-read the bit about new plugs etc so probably disregard this bit

[SteveR]

Hi All,
I have a Derbi Terra 125 that has been on the shed for quite a while. I got it out now for a full service prior to sell it, although I'm finding a very strange problem that didn't happen when I stored it. Bike starts on the button, sounds OK, has new air filters, new fluids all over, new fuel, battery, spark plugs, etc. Although, when I put it in gear it cuts off. I checked the side stand switch and it's fine. Another strange thing is that it rolls when in gear, offering very little resistance even in 1st gear. I tried to start it in 1st gear, without clutch in and the rear wheel starts rolling for a few seconds and then cuts off, although it pulls but it's not strong. I suspect the clutch plates might be stuck, even though the bike was stored with oil.
Any suggestions would be appreciated.
Thanks

The bike ticks over OK until you engage the gears?

Pull the side cover off and have a look at the clutch properly?

[Hugh]

Greetings,

Not sure if this link might be of use to you;



Note that there is specific reference to the alignment of the clutch plates.

TTFN

Hugh.

[steve the grease]

Sounds like your clutch plates are all stuck together. This is quite common on a lot of bikes and cars which have stood. Pull in the clutch drop it in gear and bang , it stops. I used to roll start mine on a hill roll gently and then just drop the bike into gear, then pull in the clutch and the alternately rev and brake until the clutch plates un stick them selves.
An aside, but, If it's been stood a while some fresh petrol will help it all along , petrol goes stale very quickly nowadays, maybe a month or 2.

[diggermanbob]

As Steve says probably the clutch plates stuck together or some of them , if you lift the bike up so back wheel is clear of ground , start the bike , put in gear let rear wheel spin , pull in clutch and apply back brake , if you do this a few times it should clear problem , if that fails strip the clutch out and clean all the plates , Good luck.

[chunky butt]

As Bob says, probably clutch, old xt660 used to do it , and recently teneres done it.......I just kept pumping the clutch with engine running and the binding clears itself.......goog luck