DT125RE exhaust problems

[jakeDT125]

Hi, I am having problems with the exhaust on my 2007 DT125RE.

after purchasing the bike about a month ago and running in the new piston

I realised that the rubber connecting the exhaust pipe to the muffler had

burst and there was an hole.

I replaced and thought nothing of it, prob. had been ready for new or something.

but now after another week of riding it has blown open again in the same place.

and I do not "thrash" the bike

any help and advice would be appreciated

thanks Jake

[Airhead]

Your silencer seems to be blocked up. Is it the original black painted steel one or an after market replacement?

[Vez]

It sounds like an after-market replacement as the standard doesn't have the rubber coupling tube like the older DTR's.

[jakeDT125]

It is the original black back box.

and seems to be original exhaust, although it has been painted silver

Maybe it has had an older model DT exhaust fitted as a replacement?

[Airhead]

You need to clean it out then, I dont think there is any sound deadening material in there??? anyone?

so take it off the bike and perhaps a blowlamp will do it...I dunno. A re-paint after though will be in order, (Plasticote BBQ paint from Wilkinsons)

[Vez]

There is no packing in the silencer afaik.

Possible water from cleaning with a jet was or similar, try and remove the small drain plug at the rear of the silencer to see if anything comes out.

The easy way would be too blow into the silencer and see if there is a blockage.

You can just make out the original DT125RE coupling in the pic below

Not a rubber in sight

Older DTR exhausts can be made to fit, and its very possible someone has, because they don't have a cat converter in like the RE exhaust does they are easier to de-restrict.

This is what is probably inside

So if it is blocked then you may have trouble unblocking it.

What does the rubber part look like? A pic would be great.

[jakeDT125]

This is the rubber connecting the two

[jakeDT125]

This is how the gap looks between exhaust and muffler

[Vez]

That looks like an older silencer and rubber gasket thing, not sure about the front pipe though.

If/when you are sure that the silencer isn't blocked it may be worth getting some tube to bridge the gap in between the pipes, maybe even an old drinks can cut and rolled (with some gun gum for assurance) and placed under the rubber would work. Just to stop the hot exhaust gases directly hitting the rubber and possibly melting it again.

I have never seen one melt before and have even used inner tube on after-market pipes and that never melted, but after-markets tend to have one pipe sit inside the other, so the short pipe may be the problem if it isnt a blockage.

HTH

Vez.

[jakeDT125]

I did use copper pipe to connect the two with gasket sealer on

then exhaust bandage but removed due to a significant loss of

power, I hope it was to do with the exhaust problem anyway.

I am looking to use sheet metal underneath the rubber and see how

that goes by the looks of things

thanks

Jake

[Vez]

I did use copper pipe to connect the two with gasket sealer on

then exhaust bandage but removed due to a significant loss of

power, I hope it was to do with the exhaust problem anyway.

I am looking to use sheet metal underneath the rubber and see how

that goes by the looks of things

thanks

Jake

Copper conducts heat at a fast rate, maybe contributing to the melting, just a thought.

Well good luck, and let us know how it goes.

[jakeDT125]

This was my temporary fix to the problem but the bike is now at the local Yamaha dealership

and have not yet heard from them about what needs to be done

[Vez]

This was my temporary fix to the problem but the bike is now at the local Yamaha dealership

and have not yet heard from them about what needs to be done

Nice little patch up . Prepare to be bent over a barrel by the dealer . On Aj Suttons website a new front pipe is £611, but i was quoted by Manchester extreme £285 for a full system.

[Ryan09]

sod that, id get a full dep system for that price....

[jakeDT125]

Sorry about the late reply guys, I haven't had time to post.

anyway the bike is back from the shop and is working fine now

this is what they did to the bike.

they only charged £20 odd so it wasn't too bad

[AndyDtr08]

Sorry about the late reply guys, I haven't had time to post.

anyway the bike is back from the shop and is working fine now

this is what they did to the bike.

they only charged £20 odd so it wasn't too bad

I cant see what they've done? Have they put some kind of sealant around it?

[Vez]

I cant see what they've done? Have they put some kind of sealant around it?

By the looks of things they have welded an extension piece to the front pipe.

[jakeDT125]

they have added a piece of pipe across the gap, its sealed with some kind of silicon?

but its heat resistant ect.

They said see how it feels and bring it back for it welding

[Vez]

they have added a piece of pipe across the gap, its sealed with some kind of silicon?

but its heat resistant ect.

They said see how it feels and bring it back for it welding

Didn't expect that kind of fix from a dealer   Think you should name and shame em tbh.

Silicone sealant* ( bathroom kind of stuff) handles very high temps quiet well, used it as instant gasket for the cylinder head before now. 

*not to be confused with frame sealant though, which tends to clog the cooling system up when it melts 

[jakeDT125]

Didn't expect that kind of fix from a dealer   Think you should name and shame em tbh.

Silicone sealant* ( bathroom kind of stuff) handles very high temps quiet well, used it as instant gasket for the cylinder head before now. 

*not to be confused with frame sealant though, which tends to clog the cooling system up when it melts 

yeah, they said the problem was due to a previous owner buying an after market silencer and having to cut down the pipe, then putting the old silencer on for sale

it was either that quick cheap fix or a new system so I opted for the cheaper option