Bike wont start

[pcooklin]

Hello - Im new to this forum and hoping someone might be able to shed some light.

I have a 50cc Kinroad XT50q. I'll spare you why I bought it but suffice to say it suits my needs, or has done until recently.

For the last year or so Ive not been able to get it to start via the auto-ignition and have been kick starting it, which has worked fine.

Recently I changed the factory air filter for a K&N style which seemed work well for a couple of weeks. I put a few additional holes in the baffles to help with air flow.

However a few weeks ago it became harder to kick start (took more kicks) to the point where the last few time Ive had to bump start it.

It now doesn't even bump start. I have changed the battery and also just fitted a new ignition coil.

Other symptoms are that it was loosing power and never seemed to get to high revs. Ive also tried different air/fuel settings via the carb and even factory default doesn't seem to get it started. I seem to be getting a spark and have tried another spark plug too.

Any ideas what I should check next.

Thank you.

Paul.

[klingelton]

check compression and check fuelling.

does the crank even turn? have you been running it with oil?

[pcooklin]

Thanks for the reply.

The crank turns. Ive just tried shorting the ignition solenoid to get it to turn over.

I did this a couple of times and then there was a massive bang from the exhaust.

Ive taken the exhaust off and there seems to be a bolt loose inside but this wouldn't be causing it not to start.

With the exhaust off it sometimes makes a popping sound as the engine is trying to fire which sounds like a build up of fuel but still doesnt fire.

It has fuel and oil. Oil was changed a few weeks ago and I checked the fuel pipe by removing it from the carb and fuel poured out.

[pcooklin]

Not knowing anything about bikes, how do I check the compression.

Thank you.

[acting_strange]

You need a compression tester...they are not expensive.....you remove the plug....push or screww the compression tester into the plug hole and turn it over....obviously if its the push in type you will probabaly need someone to help.....you then check the reading against what it should be...

Here is a video

[pcooklin]

Ive just checked the oil and although I did an oil change a few weeks ago there didn't seem to be much in there. There's no real oil leaks so Im not sure why it was like that as I filled to the factory level. With oil topped up, when I crank the engine, there's now a 'swimming' sound. Does this mean too much oil?

I watched the video, thank you. Not sure how much more to invest in this personally as the bike from new was £600. Ive had it over 3 years and have replaced a few parts.

Im tempted to take it to a garage but with labor costs at £40 per hour Im wondering if its worth it. Ideally Id like to fix it myself but my lack of knowledge is prohibitive.

I will look in to a compression testing kit.

Anything else I could check for myself.

Thanks again.

[acting_strange]

Your rings and valve seals could be shot causing you to burn the oil...which would mean its time to go, the bike that is .....not worth the repair....

[klingelton]

Your rings and valve seals could be shot causing you to burn the oil...which would mean its time to go, the bike that is .....not worth the repair....

 

Would explain the gradual drop off of power and burnt oil.

I didn't ask if it was 2 stroke or 4 stroke - i just assumed it was 2 stroke!

Easy way to check compression is to remove the plug and put your finger over the hole. turn the engine over and your finger should be blown away with some force. if you're able to hold your finger in situ, the piston/rings are shot.

[acting_strange]

Your rings and valve seals could be shot causing you to burn the oil...which would mean its time to go, the bike that is .....not worth the repair....

 

Would explain the gradual drop off of power and burnt oil.

I didn't ask if it was 2 stroke or 4 stroke - i just assumed it was 2 stroke!

Easy way to check compression is to remove the plug and put your finger over the hole. turn the engine over and your finger should be blown away with some force. if you're able to hold your finger in situ, the piston/rings are shot.

 

Your valves could be burnt out as well which would give the same symptom of no compression...just for info

[klingelton]

Your rings and valve seals could be shot causing you to burn the oil...which would mean its time to go, the bike that is .....not worth the repair....

 

Would explain the gradual drop off of power and burnt oil.

I didn't ask if it was 2 stroke or 4 stroke - i just assumed it was 2 stroke!

Easy way to check compression is to remove the plug and put your finger over the hole. turn the engine over and your finger should be blown away with some force. if you're able to hold your finger in situ, the piston/rings are shot.

 

Your valves could be burnt out as well which would give the same symptom of no compression...just for info

 

excellent! forgot the valves!

[pcooklin]

Ive just put a cloth around my finger and inserted in to the hole. There was 'some' pressure but not enough to push my finger out. Whether that's 'enough' I dont know.

Your verdict sounds correct and would make sense to my non-mechanical mind. I would imagine running it flat out with the new air filter, adjusted carb and holes in baffles has probably killed it, which would be my fault trying to get it to go a little faster.

It's a 4 stroke by the way.

[acting_strange]

Ive just put a cloth around my finger and inserted in to the hole. There was 'some' pressure but not enough to push my finger out. Whether that's 'enough' I dont know.

Your verdict sounds correct and would make sense to my non-mechanical mind. I would imagine running it flat out with the new air filter, adjusted carb and holes in baffles has probably killed it, which would be my fault trying to get it to go a little faster.

It's a 4 stroke by the way.

 

I would hazard an educated guess that you have possibly scored the bore by running too lean and hot due to the K & N etc....ruining the rings and even possibly the valves...of course it could just be the head gasket gone but from all the other descriptors I don't really believe that...

[pcooklin]

Yes, that would make sense, either way it's dead.

What's great is that I have just bought and built a bike shed specifically for my moped.

Ive also just past my CBT as I had been running around on my moped for the last 3 years on my car license which has a P, but not realising that I missed the qualifying date (2001) by a few months, so took my CBT a couple of weeks ago (Im 42). Now that Im legally aloud to ride my bike and have a great home for it, I no longer have a bike to ride.

It's a shame, I did like that moped with its chopper/cruiser styling but looking at this another way, Ive learnt quite a lot about bikes over the last 3 years, more than I did before getting the moped, and have enjoyed the learning curve.

Thank you again for all your help and contributing to my knowledge.

[klingelton]

Well that's a bloody shame!

have a look on feebay and see how much a replacement engine is for one of those - and if it's worth replacing. You could just look at a 125 instead though - if you can afford it.

[pcooklin]

Ive been told that a Honda Cub 90 engine fits.

A new engine is around 350 quid.

I'll look around for another but Im now wondering if a 125cc might be the way forward as Ive just seen autotrader selling a few for around £500 which might suit my purposes.

Thanks again.

[klingelton]

If the c90 engine fits, there's a 110cc pit bike engine that will fit also. It's a china engine, but massively cheap. Have a look on the web, loads of people have done this.

[pcooklin]

Do you know the name of the engine/bike. I'll try searching.

Thank you.

[klingelton]

just search ebay for a honda pitbike engine. This will yield a plethora of single cylinder engines of varying sizes that will most likely fit your bike. it's a fairly common lump and changing out yours should take some minor fettling. It seems they can be got for around £100. i'd be tempted to roll back to a more stock air filter as well.

[pcooklin]

Ive decided to buy a new Honday CBF125 because for many reasons this is what I should be riding.

[klingelton]

good choice. the CBF125 is a great looking and affordable bike. excellent mileage. you should have a great deal of fun on it!

[pcooklin]

When I recently took my CBT there was a young guy who had a CBR, which looked very nice, but when I had a go it didnt feel quite right. I think perhaps because Im 6'2 and from what Ive read the CBF is better suited for taller people. Im looking for the best deal but it seems like the right choice given my needs.

[klingelton]

CBR is a sportier bike, CBF is a bit more upright. at 6'2" you could look at a varadero, if honda is your thing. They're completely deceptive (look like a big bike) and have those big bike dimensions, which also means are better suited to larger people. They do tend to hold their value well, so if you havn't got alot of money, it might not be ideal.

Just a thought.

[Tango]

CBF is a good bike.......CBR is OK.....but you'd pay a hefty price on insurance for that "R" in the name......