Jump to content
This post is 4234 days old and we'd rather you create a new post instead of adding to this one. You can't reply in this post.

Recommended Posts

Posted

hi all...

thursday night/friday morning going to work noticed a few strange things happen to my little dtr ill try explain in detail see if you lot have any ideas.

right heading into work thursday i noticed the bike wouldnt go past 6krpm would bog and pop out the exhaust while pulling aggeresive in spurts go up a gear no problems aslong as i keep below 6k rpm now i posted in a thread about fake iridium plugs and i did have this problem with 2 of the iridium plugs i bought off fleebay but the original ngk plug was fine - now its doing it with all plugs grrrrrrrrr

whilst parking her up leaving her to idle i noticed what i can say is a knocking noise coming from the topend but would come and go but the noise was noticable easily

i put the poor running down to a blocked main jet maybe??

unfortunatly i had no option but to use it to get home exactly the same was lucky to get 40mph and she just felt all wrong (a complete chore to ride)

same goes for friday i had to use it as i didnt have any means to get to work then same same bog pop pop bang blurgh up a gear no problem however when i got into the yard she just cut out completely rolling to my parking space.

now friday after work 15mins of kicking and bumb starting absolutely nothing.

checks ive done

plug (changed)

filter (nice and clean)

fuel (drained float bowl and there is a constant flow of fuel)

im ordering a new mitaka topend kit along with small end bairings and athena gasket kit just worried incase this problem is an easy fix and im getting a little carried away wasting money

cheers

ken

Do you want an ad-free experience? Join today and help support the Yamaha Owners Club.
  • Moderator
Posted

sounds electrical to me Ken, whats the plug cap to HT lead connection like...maybe cut off 10mm and re-make and spray the lead/cap with WD40 ?

Posted

you think? how come its coming in at a certain rpm? i thought it was more the fueling system but hey if its the ht lead even easyer to fix although i have had the plug out and checked for spark

cheers

ken

Posted

just a thought! bad fuel ? maybe a of water in it

  • Moderator
Posted

Hows the oil situation. Perished feed pipe could let air in but not let oil out. Sounds odd but its happened to me on the DT.

Intermitant knocking and performance. I have had the very same thing before.

The knock you say its easy to hear. Would you class it as a deep knock coming from the whole of the motor.

I would be preparing the wallet. From what you have said it sounds deeper to me. More crank seal, big end related.

Posted

bad fuel was my first guess...

to be fair the bike is in very good condition all pipes still flexable and usable oil is getting there, could there be something wrong with the reed block? i fitted carbon reeds on it months ago just wondering if they have failed?

the knocking noise is a light sound coming from the topend - sounds like barings are shot

unfortunatly i dont have a wallet at min due to child, mortgage and the significant other dropping 2 days at work :(

ken

  • Moderator
Posted

Right light noise from top end sounds far better.

If you can pull the top for a look.

If its a broken ring you could be 1rpm from total engine failure. The melted piston on my dt required new crank bearings. And the ovbvious full engine strip. The reeds wont cause the tapping. Could be the little end.

Posted

i done the whole topend less than 500 miles ago - i didnt use a decent branded kit but ill have to look at a mitaka topened and some quality small end barings but sure the dam thing shouldnt have given up after 500 miles??? i do change plugs every other month and there golden brown in colour!

ken

  • Moderator
Posted

Tear the top end down for a lookie see.

Mechanical noise is always worrying. Poping and banging with the. Lets call ot tapping mean something is up.

They are easy to strip and if its all good the other options will feel more permanant. You have prob lost a little faith in her now.

  • Moderator
Posted

I've see a few DTR's with burned and smashed pistons where the exhaust port is, another easy to do thing is to take off the exhaust and have a look at the piston front/top through the port

Posted

Yeh cheers lads...

I'm loosing faith in her a little, for a 2t that bike was so reliable wanted nothing took some punishment.

My little dt125 with some michelin AC10's on will go anywhere but I have to admit once I get her fixed up she is gone!

I'm going back to the honda nsr 125 jc20 or an tzr 125 just for a change in bike style however I can't say a bad word about my little yammy.

If its not raining tomorrow I'm gonna push her home even though its all uphill for 2-3miles (gulp)

Cheers

Ken

Posted

I'm no mechanic, but have you checked the fuel cap is breathing? May explain no high revs if fuel is vacuumed? Like I said, I'm no mechanic and I'm probably talking out my arse!

Posted

that is a good coment but the bike wont run at all now and there is fuel flowing out of the drain screw pipe at a fast rate...

cheers

ken

Posted

If you know anyone with the same model, swap over the CDI unit. The symptoms were the exact same as my sons SR125 and twas the CDI that was gubbed

Posted

Unfortunately the only way (I know) to test is by replacement, but as I say, you have described the exact same symptoms the boys' bike showed

Posted

Hey ken over fueling will cause all kinds of prob's could just be a stuck float/worn seat valve. Although the fiber reads I have seen break and cause quite a mess.

Hopefully the wind will be at you back for that long push.

jimmy if anyone ever finds a way to test CDI units other than replacement let us all know,I have tried to take them appart but everytime I get them appart I cant read the printed board or the colour codes on the resistors and cap,for somthing that is/would be so simple to make it's top secret LOL

  • Like 1
Posted

Yea I know, I tried with a few on t'lads bike, to no avail

Posted

Good (ish) news

Got the back bike in back of van, took off exhaust piston and rings still intact, powervalve fully functional-spark coming from plug so its got to be fuel side of things...

Strip down of carb this weekend me thinks

Ken

  • Who's Online (See full list)

    • There are no registered users currently online
  • Recently Browsing

    • No registered users viewing this page.
×
×
  • Create New...