crankset guard bolt patterns??

[audiobull]

hi all
ok so ive got myself a giant terrago trail series and everything is great on it. i do however wish to upgrade the gaurd on it to a slightly stronger less flimsy one. However i have been looking at the blackspire ones and they list there is a few bolt pattern sizes. i have looked everywhere on the crankset and guard to no avail. it is a TruVativ ISOFlow (22/32/44 sets) and the guard is a auroguard with 4 screws on it. how do i tell what pattern sizes they are?
blackspire list
146
110
104
94
so stuck to which one to get as they also list
104, 94 fit 42t – 44t rings
110 fits 44t – 48t rings

here is a pic of my crankset at the moment

 

[Steve Austin]

Mr Bull measure the distance between two holes and it will equal one of the measures on the left, and the measure on the right is the size ring you want.
34.1mm 58mm
43.6mm 74mm
50.6mm 86mm
55.3mm 94mm
64.7mm 110mm
71.7mm 122mm
76.5mm 130mm
79.4mm 135mm
84.7mm 144mm

HTH

 

[Steve Austin]

But you may find you may not be able to fit a guard and keep all 3 rings.....

 

[audiobull]

i have between 1 screw 79.4mm and the other 110mm and diagonally to each screw 135mm so am i looking at the 79.4mm 135mm you mentioned above and how does that link with the 146,110,104,94 blackspire list? am i looking at the 110?
thanks for great advice so far and quick response

 

[Steve Austin]

Not sure you are measuring right there...

You need to measure the distance between the two chainring holes. so number the holes in a clockwise direction, 1,2,3,4. you need the measure between 1 and 2. this will give you the chainguard size.

BUT most chainguards sit where the outer ring is, so you will lose the outer ring on your chainset

 

[audiobull]

the one on there at the moment is mounted on the outer ring by 4 screws and not mounted on the ring itselfs mounting points (see pic for where there mounted)
does it mean by changing the chainguard i lose my 3rd large ring? i thought they might have just been interchangable except bolt patterns. should i be measuring the larger holes/bolts just inside of where ive marked red?

 

[P.H]

If your crankset is this one then the BCD is 104. A Blackspire ring guard will fit to the chainring bolts rather than those screws. Get one that specifically says it's for a triple, it'll have a cut out for the crank.
However...before you spend any money, think about what you need. Anything by Blackspire will be designed to protect the chainring from damage when out mountainbiking. What you already have fitted is designed to keep your trousers out of the chain and a bit of oil off, these are always a bit flimsy, that's fine. I wouldn't change it unless it broke and then I'd consider if I needed it at all.

 

[audiobull]

ok thats brill. so steve was right in saying about measuring the large holes rather then the scews. i think i will go for one and see how i turns out when out riding. i will update when/if it goes on ok. big thanks to steve austin and P.H for all your help