Intruder Airbox

[greeno]

Picked up a rat rod '80 Intruder.  Runs on spray and should be running shortly. 

The manuals from most sleds say "Don't run without the airbox".  Why?  Can I just slap some filters on the carbs and go? 

[kawhead]

stock intruder carbs have a powerjet circuit and need the vaccum the air box provides.you can pod it and re jet but imo not a lot of gain.

[greeno]

Thanks Kawhead. 

Care to be a little more specific?  Will it run at all without the airbox?  Should I not even try without the airbox? 

[gixxer6]

It will run without the air box.  But without it, there is less vacuum in the carbs which is required to run the power-jets correctly.  So you'll either need to re-jet to adjust, switch to non-power jet style carbs, or find an air box.  Otherwise the engine will run lean, and possibly melt down.  IMO with the stock pipe and no air box (or with pod filters) the engine sounds terrible.  It's a very loud boggy sound.

[greeno]

Gotcha.  I can see if this rat will run (without an airbox), but don't take it on a vintage ride until I address the issue.  Maybe set the needles all the way up while I wait for an airbox. 

[gixxer6]

Be careful, the power-jet splits the main circuit, raising the needle won't help at WOT... 

If you need an air box, PM me, I might have an extra I'd sell.   

[greeno]

PM sent.

[kawhead]

no wot without an airbox and stock carbs,,,,too much thermal efficentcy