Problems and Questions (Yamaha DT125 2 Stroke) - New Problem Post #15

Dragonistic

Dragonistic

5,677
United Kingdom
United Kingdom
Dragonistic
Ok, hopefully someone will have some idea what to do with my bike. After the exhaust needed a change, I had to go off to uni for a while (couple months) and during that period my stepdad changed my exhaust for me. Now though when you turn the ignition on, press the start button and nothing happens. The spark plug appears to be ok, and you can attempt to start the bike manually using a screw driver and bypassing all the electrics in doing so but it still won't start.

The only thing I can think of is a dodgy problem with the killswitch which is stopped it from turning over properly, as I've noticed if someone does (or did I should say) hit the kill switch on my bike then it won't start for a few minutes after, it does nothing at all on the button for that period.

Any suggestions would be greatly appreciated.
 
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Dragonistic
The only thing I can think of is a dodgy problem with the killswitch which is stopped it from turning over properly, as I've noticed if someone does (or did I should say) hit the kill switch on my bike then it won't start for a few minutes after, it does nothing at all on the button for that period.
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That would certainly make me suspicious of the kill switch. If the kill switch is operated, there should be NO delay after switching it back.

Another thing to check would be the sidestand - some bikes have a safety interlock which prevents you from selecting a gear when it's down, for example. The sidestand switch is down close to all the crud and can sometimes malfunction,

Does your bike have a kickstart?
If so. it would be worth removing the sparkplug and kicking it over to check for a spark.

Good luck,
Phil
 
We checked for a spark using the screwdriver, it sparked, but the side stand is a good idea. Will check later.
 
Apologies for the double post but it's been a few hours and I did some testing, the stand was fine but was definately worth a shot. Turns out the killswitch was the cause, after messing around flicking it on and off whilst holding the start button it woke up right away and started great. Just needs an MOT now which should be... interesting. Will also look how much a new switch costs.
 
Enjoy getting muddy :D

used ones on ebay go for about a tenner but I'd be tempted to take it apart and clean it up...I am a cheapskate though
 
I won't be getting muddy, mine's the SM (Supermoto) and I don't race it on the tracks so it stays on tarmac, I've posted pics in and around this section so I won't post them again, but you can find them in my album from my profile 👍.

I just came off eBay, but I think a replacement is neccessary as we did take the switch apart and clean it up and such but it was still faulty. Hopefully the switch is no different between the models (R, RE and SM), you would think not but the exhaust is ever so slightly different in its fitment.

Thanks for the suggestions Phil, appreciate it. Neither me nor my stepdad are bike experts so the killswitch is unknown territory on the specifics of it so we were riding on suggestion with no real knowledge. Also, you have the greatest name ever, I mean everyone knows all Phils are just fantastic (doesn't take a genious to work out I'm also a Phil).
 
Nice 👍 Wash you bike ;)

It might be worth pricing a new one, they might be prone to failing.

I've just had a flash back of a great road not too far from you. The B4391, it's between the A4212 from Bala and Ffestiniog.
 
I do wash my bike, I just hadn't when I took those pictures :sly:. I'll have to see if anyones up for a road trip some time around me, I do know some good roads, hell I practically live on them where I am (don't live in town). Once I get that MOT done I'll be going straight to my buddies in Telford for a week or 2, but after that I have plenty of time to enjoy the open road.
 
Indeed, you're much better placed for great riding on your doorstep than me...I'm not jealous at all :ouch:
 
It's true, I'm spoilt for choice when it comes to most commutes I have to make. For example when it comes to my little trip to Telford (roughly 40 miles) I can either book it down the A5 which is an ok road, or I could wind my way parallel along fantastic country roads. The downside of that trip is Telford is packed with patrols now, not that I'm an avid law breaker or anything, but they like to pull bikes like mine to check if they're stolen, just an unneccessary possible hassle.
 
Well, I just had my MOT and it failed, chief problem being a leaky shock seal on the front. Cheap parts but to complicated to fix myself which is a shame, everything else is very minor and I could do myself with no parts. Never mind though, could have been worse.
 
Bah, my first dirt bike had NO oil in the forks and it never did us any harm...apart from that time I nearly shattered my ribcage on the bars after a particularly ambitious jump! Actually thinking about it, my Dad probably could have done a better job of looking after us than let us rag around on a knackered little put-put at the age of 12!

It's a pain failing a MOT but buggered suspension isn't really safe. My Bandit failed on loose rear linkages, turned out all bearing had disintegrated! After a lot of cash, swearing, angle grinding and blood it passed and was much smoother for it.

I've replaced fork springs before which is easy but it can be tricky getting the stanchions out so probably best getting someone who knows what they're doing to sort it out.
 
There are minor jobs which are easy to do, the following:
Rear wheel alignment, adjusters just need a tweak
Headlight is aiming 5mm low (seriously? I could switch high beam on and that would be fixed! but I'll do it right)
Rear reflector blocked by my L plate currently, there's nowhere to put that damn L plate I wish I could just afford my full test but I'll find a spot.

That leaves only the shock of the neccessity, there's referrals for slight pitting on the front fork, front pads on their way out soon ish and something else which slips my mind but is also minor (or it wouldn't be a referral!). Overall it's not to bad, it's a shame I can't do that seal myself as they said oil and a new seal would only cost £15 total, but I'd be paying them upwards of £60 for the job. I'll see if I can get it done cheaper but ultimately it's not to bad overall.

There's also a slight problem with the stand, they couldn't get the stand up without putting the kill switch on so when they put it in gear, it shut off. I walked around back and got it going first time which really surprised me that they couldn't do such a simple thing (just give it a fair old shove when putting the stand up, despite one guy saying he gave it a good kick) yet they notice my headlight is aiming 5mm low!
 
Quick update, the bike is now ready to go back for it's partial MOT after taking a visit to the repair shop, I'll be picking it up in the morning and having the MOT same day. The only bad part is the bit where I'll get the bill :scared:
 
Thread dig up time, I have a new problem. When I say new, I mean not new but I've not been using the bike much so had no need to worry.

Essentially the bike will not rev under certain circumstances, though the next day it will rev freely all day long. Details following:
- Will not rev freely when given more then a sliver of throttle, can start normally sometimes and then begin to fail later in the journey. Power totally cuts once too much (not much, more then 10-20% or so twist) throttle is applied.
- Alternatively will not rev once started unless given small throttle similar to above, though this happens less.
- Will rev more freely with the choke on, though still not fully (perhaps up to 40% twist on the throttle).
- Problem can disappear again randomly later in the journey.

Anyone have any ideas? It seems totally intermittent and random, essentially it can happen any time the motor is put under load and generally occurs on the move, power is completely cut when the problem is happening until the throttle is released again rather then a gradual power drop it's like a switch.
 
Headlight is always on anyway, can't be shut off. All electrics seem to work fine though, surely the amount of load on the motor wouldn't have a massive effect with an electrical problem (you can still rev as far as you want, you just can't give it much throttle, I was thinking fuel problem). I'll look into it though.
 
Dragonistic
(you can still rev as far as you want, you just can't give it much throttle, I was thinking fuel problem).
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Ah, I was thinking that you meant it as though you couldn't rev it.
And if the battery and other electrics like the alternator are shot then it won't be able to run at high throttle openings. Our kart had the coil go on it and it would idle fine but as soon as you gave it gas it would stall.

And yeah, try cleaning out the carb, if you haven't ridden it in a while then it could be gummed up.
 
I haven't recently clean it, but we had before when the problem was around. The problem is everytime I try to take it to a shop it works perfectly so the problem is impossible to identify for them.
 
Well the problem appears to be fixed, I took it in for MOT with a great local guy around the corner (who does repairs but not MOT, he takes it to another local shop for the MOT who has a grumpy guy I don't like so I don't have to deal with him myself this way!). He's added some 2 stroke straight in to the fuel and topped up the tank and he believes the float in the carb was sticking which makes alot of sense given the circumstances and randomness of the fault so he simply tapped the side of the thing whilst turning the motor over and it appears to have completely cleared. With some additive in the fuel and the extra 2 stroke roaming around it should prevent it happening again for a long time hopefully.

Also passed the MOT so I am back in action fully 👍, the limp to my interview in Wrexham today having to ride on full choke under low throttle going to the top of every gear so it sounds like I have 2bhp max whilst not being able to release the throttle fully for any more then a second or stall was a pain :lol:.
 
It was interesting :lol:, fortunately with the non-stock exhaust it's not to tinny. Bikes running super smooth now though, like having a new motor 👍.
 
These things are meant to be used Drag.

Especially two-strokes.

If you don't give it a good ragging now and then, expect problems.
If you rag it too often, expect problems.
If you are going to park it for a while, FILL the tank.
If you are going to park it for a year, DRAIN the tank, and make sure it's sealed.
Running your bike low on fuel will drag (no pun intended) all the crap through your fuel system that is currently residing in the bottom of your fuel tank.
Change your filters regularly, and carry a spare plug and plug socket/spanner.

Lastly, clean your bike a lot.
If it knows you love it, it will get you where you want to go.

That last bit might be just in my head.

That's about all I knew when I was running a two-stroke, and I got everywhere I wanted to, most of the time, for years.

:irked:👍
 
I'm fairly good at doing all of the above but I should probably clean it more often if it was so darn awkward getting in to all the tiny gaps and such but that being said I'm not commuting these days so it isn't doing any long journeys, out every 2-3 days. For example as regards running on low fuel, I've only ever used the reserve tank once. Ultimately I think the source of this problem was lack of use in general, over the past 3 years it's only seen a few random rides here even though I tried to take it out whenever I could and there with university whereas now it's back in regular use it shouldn't happen again.
 
I didn't even know you'd owned bikes until that post :lol:, what 2 smoke(s) did you have?

Fortunately for me I could still get anywhere I needed to go with the problem, living away from the bike definately didn't do it any favours though but now it'll be in action pretty regularly, daily once I get hired until then I'll just have to hoon about the countryside for no reason (what an awful shame :sly:). I've been plagued with various problems over the years with mine since I got it, including having it taken from me for being a stolen vehicle 👎. Hopefully my problems are over for a while now.
 
Heard of a Fizzy?

Thought not.

I'm twice your age man.

Well, nearly.

Or something.

I had two strokes before you were born.

God that's scary......

:irked:👍
 
You're a good 7 years from double 👍, also I have heard of a fizzy (Yamaha FS1E?) though I can't say I've seen one. Off topic I need to start playing BF with you guys again.
 
Dragonistic
You're a good 7 years from double 👍, also I have heard of a fizzy (Yamaha FS1E?) though I can't say I've seen one. Off topic I need to start playing BF with you guys again.
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My old man used to mess about on the FS1E's or Fizzys back in the day.
he used to get them going alot quicker.
 

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