Please help! Dtre 07 not working properly?

[henkkqa]

Hello, my dtre has a strange problem and ive tried everything to fix it nothing has worked.

Problem is that it backfires through the exhaust not carb side.

Originally the problem was a blown head gasket since during a ride w my dad my dtre over heated and blew the gasket, i got new gaskets and also resurfaced the head, yet still has the same peoblem

I've confirmed it gets gas, spark and everything else it needs.

Ive tried
New plug
New coil
Adjusting the timing (i have HPI igniton)
New reeds
Also has a new piston set.

I need to fiqure out whats the problem so i can finally start going to work with it.

Any suggestion or advice is really usefull

[Calum]

What head gasket did you use?

If the new head gasket was white in colour then it's probably the same culprit as the cheap head gaskets simply do not work. Use genuine, Athena or Vertex head gaskets only.

Did you install the head gasket with UP facing you? The head gaskets can be accidentally fitted upside down, which again will cause similar problems.

When you say New coil you mean new genuine coil. Again the knock off chinese Racing coils DO NOT work. So only use genuine ignition coils.

I don't know what a HPI ignition is, but if you can source an OEM ignition system you can rule out faulty electronics.

Common problems on these engines will be things like, waterpump seal leaking into crank case and then crank seals leaking into engine combustion chamber. Both are pretty obvious but will cause running problems. And when I say common, they don't come up that often as the engines are pretty darn bullet proof.

[henkkqa]

@Calum athena head gasket is what i have and everything is fitted right, not sure what i meant by new coil since it was pretty late when i made the post but definently a new plug is in. Ive tried everything and havent had any progress. HPI is racing electricals which arent chinese, so all the wiring is custom made for lights and such but kt doesnt support 12v DC.

Still same problem that it backfires, starts weakly when bump starting and kickstart doesnt even promise

[Calum]

Well this makes it challenging to diagnose if it's got a custom wiring loom on it.

Have you ever had it running right. When I hear custom my first thoughts are, well it's probably something to do with that then sadly. As these bikes are very simple, the things to check are the basic two stroke principles:

• Compression
• Ignition
• Fuel

And if you've got all those then it'll go.

So what's the compression of the engine?

If it's got a custom ignition system then what's the static angle been set to?

I wouldn't go round forcing it to start, it should start first/second kick with choke and anything else you're going to do more harm than good.