valve recession & dust
this seems to be the forum with the more knowledgeble people so that´s why I post my questions here:
I live and work in Portugal and offer guided offroad trips.
Currently I own 6 KTM´s, five are 2003 EXC models. On all these EXC bikes I replaced the inlet valves and on one bike also the cilinder & piston rings after one year(my first year).
The foam filters used in todays dirtbikes doesn´t seem to get rid off the finest particals.
I pinpointed the cause to the fine claydust (powder) that destroyed valve and in a lesser way the seats. On all bikes the rings were also beyond specs.
I´m familiar with the correct cleaning and oiling methods, I use Twinair products. I use a standard, oiled filter + dry dustcover + skin. I make sure he filterholder is in the right position.
Still dust seems to pass the filter from the moment I start the engine and ride in dusty conditions.
I know this because there´s a fine layer of dust covering the flame arrestor mesh wire on the filter side.
I spend the last few days browsing forums and widen my knowledge. I learned a lot about valve materials and combinations of materials.The emphasis is put to the tuning of the engine and little thought has been given to airfiltering in the documentation that I found about tuning.
My question(s):
is there any info to the size of the smallest particals that are trapped by a foam filters on the market today?
Can anyone point my nose in the right direction concerning better filtering methods (if they exsist)?
where can I find info about the theories of airfiltering?
--------------------
I
am aware of the fact that lifespan of the engine is not the biggest isue when it comes to dirtbikes. Nevertheless I hope to find a way to overcome this problem.
High power output is not my goal. Durability is what I´m looking for.
Adriaan, spelled my username (dustbite(sic)) wrong, found out too late....
this seems to be the forum with the more knowledgeble people so that´s why I post my questions here:
I live and work in Portugal and offer guided offroad trips.
Currently I own 6 KTM´s, five are 2003 EXC models. On all these EXC bikes I replaced the inlet valves and on one bike also the cilinder & piston rings after one year(my first year).
The foam filters used in todays dirtbikes doesn´t seem to get rid off the finest particals.
I pinpointed the cause to the fine claydust (powder) that destroyed valve and in a lesser way the seats. On all bikes the rings were also beyond specs.
I´m familiar with the correct cleaning and oiling methods, I use Twinair products. I use a standard, oiled filter + dry dustcover + skin. I make sure he filterholder is in the right position.
Still dust seems to pass the filter from the moment I start the engine and ride in dusty conditions.
I know this because there´s a fine layer of dust covering the flame arrestor mesh wire on the filter side.
I spend the last few days browsing forums and widen my knowledge. I learned a lot about valve materials and combinations of materials.The emphasis is put to the tuning of the engine and little thought has been given to airfiltering in the documentation that I found about tuning.
My question(s):
is there any info to the size of the smallest particals that are trapped by a foam filters on the market today?
Can anyone point my nose in the right direction concerning better filtering methods (if they exsist)?
where can I find info about the theories of airfiltering?
--------------------
I
am aware of the fact that lifespan of the engine is not the biggest isue when it comes to dirtbikes. Nevertheless I hope to find a way to overcome this problem.
High power output is not my goal. Durability is what I´m looking for.
Adriaan, spelled my username (dustbite(sic)) wrong, found out too late....
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