DR650 Exhaust question

[Matie spero]

As die exhaust port so klein is, help dit dan enigsins om die header weld te grind, behalwe as jy natuurlik 'n vol gas flow op die head doen.


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Chopper

Dit is 100% hoekoem ek die vraag gevra het. ek het fotos gesien op die interwebs waar daar werlik baie groot obstructive blobs is, maar in 99% van die geval is dit nie so nie, en dan maak dit nie veel sin om die weld weg te grind nie.

[Matie spero]

You should only grind the weld's end blob (if there is a significant one), not the whole bead. Grinding the bead weakens the weld significantly.

Lecap
I did not have a significant blob, but also did not grind the weld away completely, left about 1mm there still.

agree that this could be the hottest part of the exhaust and would require a proper weld for structural integrity.

[chopperpilot]

As die exhaust port so klein is, help dit dan enigsins om die header weld te grind, behalwe as jy natuurlik 'n vol gas flow op die head doen.


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Chopper

Dit is 100% hoekoem ek die vraag gevra het. ek het fotos gesien op die interwebs waar daar werlik baie groot obstructive blobs is, maar in 99% van die geval is dit nie so nie, en dan maak dit nie veel sin om die weld weg te grind nie.

[Kykdaar]

No blob = no grind.

Now go and put your bike together so we can go for a ride

[Matie spero]

Heres an interesting read:

http://drriders.com/topic2360-30.html

[Matie spero]

No blob = no grind.

Now go and put your bike together so we can go for a ride

as dit van my af gehang het was sy al lankal aan mekaar...

dis n fyn balanseerings oeffening tussen haar, mamma gelukkig hou en tyd....

[lecap]

Heres an interesting read:

http://drriders.com/topic2360-30.html

What scares me about this article is that the author does not see a gasket even if he takes a VERY clear picture of it

If you're really that hot in pursuit of some extra power you should maybe DIR and cut the flange off the header below the clamping ring, machine a new flange on the lathe with an inner diameter matching the port and then TIG weld it back on from the outside. If you do this right you will have a 100% quality strong weld with no significant protrusion to the inside and very little protrusion to the outside. The problem with the OEM weld is it's MIG and done from the inside likely for cost reasons.
Grinding around on a weld is a no no. It's kind of acceptable to clean off an over sized end blob. As long as it's not a structural weld.

[Matie spero]

here's also something interesting:
but requires an extreme technical knowledge:

http://dairally.net/daihard/chas/MiscCalculators/DaiPipes.htm

and some more (I found this probably the most useful):

http://hotrodenginetech.com/porting-pointers/

anybody keen to do some maths??