Cowl Attachment - Xigris

[Stuart Mellor]

Hi all,
 Faced with attaching the cowl/underbelly on my new Xigris, I did not want to use those dreadful 3mm bolt attachments at the front. They are a pig to fit & relocate & it takes too long to remove the cowl in an emergency. The piccies should explain – I used a 3 mm tongue & slot at the front & at the back there are 2 D shaped pieces of ply which can rotate. As they rotate they engage & trap the bottom flange of the cowl for a very secure fitting, using a ball driver thru the cooling slots. It now takes 10 secs to remove & refasten the cowl!

Stuart
PS – my u/c is in the wing, but if using the conventional carbon u/c, there should still be room just forward of the u/c, but in any case you need a 1/16 paxolin tongue & slot immediately in front of the D plates to prevent the cowl spreading when tightening down.

[Stuart Mellor]

Had a big 'Ahah!' moment recently - (as opposed to an Aaaaagh!). My CDI never seemed to be cool enough & exhibited strange noises at times, when pulling up sharply. Couldn't get to the bottom of it - THEN - the o ring in the silencer sprung a leak & exhaust goo was coming out of the top cut out (made for insertion of glo clip in emergency) instead of the rear cut out, even though the goo had to travel forward some distance to exit.
I had made this delta shaped & large enough not to expererience cowl damage after a backfire.
What I had not realised until now is - that the majority of the cooling air was exiting thru this cut out instead of flowing to the rear of the cowl!
Have now enlarged the holes at the rear & cured the problem! I reckon this was also causing unstable air to enter the carb at times causing strange effects.
In future any holes in the top of the cowl I will make small!
Stuart