www.gpz-305.de

Kaarel · Verfasst am: So Mai 25, 2014 10:49 am Titel: Rattling exhaust

I have stumbled upon this typical failure: rattle in right exhaust. I did search the forum, but I couldn't understand, if there was a solution.

Shouldn't there be a balance pipe for connection between the exhausts? Maybe that balance pipe has became loose?

I'll probably try cutting it open after the season.

// Oh, and it seems to be in the exhaust header, not the muffler.

Thanks in advance
Kaarel

Frank · Verfasst am: Fr Jun 27, 2014 10:47 am Titel:

The header ist a double pipe. Its to protect the black chrome at the 305. Nearly every older japanese motorcycle protects the chrome on this way.

Its welded at the front and the end of the header. Sometimes it breaks.

Easy way: Drill some holes in the header an weld it.

Hard way: Buy some new.

Kaarel · Verfasst am: Mo Jun 30, 2014 3:45 pm Titel:

I went the semi-easy way: I cut the pipes and welded it all together. The rattling kinda remains, but I can do some more welding.

Frank · Verfasst am: Do Jul 03, 2014 3:10 pm Titel:

Are you sure, that the rattle is from the header? One of my mufflers broke down inside.

It seems, that the rattle comes from the pipe between the Headers, but it wasn't.

I used am Motad 2in1.

Kaarel · Verfasst am: Do Jul 03, 2014 5:32 pm Titel:

I didn't plan so, but I ended up cutting into 4 parts:

Finished product without paint:

Muffler seemed to be OK, but I'll check it:
My plan is to cut muffler off and then turn on the engine (around 3500 rpm the rattle occurred). If rattle remains, then the problem is in the header.

SRadi · Verfasst am: Fr Jul 04, 2014 7:41 pm Titel:

Very interesting - please give us more information with pics

Kaarel · Verfasst am: Fr Jul 21, 2017 8:43 pm Titel:

Sorry for not replying. I didn't do anything with my bike for two years. But here I am again, trying to get her on the road again.

In the beginning (pics are clickable):

A crack inside the exhaust (near the cylinder):

Tried to weld it from the existing hole in the middle of the exhaust (it was a bit messy):

Then I decided to make a small cut which I welded later (I only cut the outer layer):

But it turned out that the rattle remained. It seemed that the rattle came from the muffler. So I cut open just below the muffler and I found that the inner muffler tube (perforated) was connected with the outer layer only at the end of the muffler. A red arrow shows the gap:

So I welded the layers together:

This turned out to solve the problem.

----

Offtopic: now I have to work on the electronics/engine. The voltage regulator wasn't doing its job and was giving out 16,5 volts. Also, the engine has no power above ~5000 RPM (especially on higher gears).