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View Full Version : Firecat TR2 IBO - ABO



kylebattell
07-16-2010, 07:11 AM
I recently purchased the Firecat TR2 and shoot 70lb draw weight, 29 1/2 inch draw length, a 300 Gold Tip and a 100 grain field point...I was curious what the expected ABO speed is considering the IBO is 335-345...I ask b/c i am getting a consistent 285-288 speed and was wondering if that is normal? Some possibilites may be the after market String and Cables ? My Axle to Axle is 32 3/4 instead of the 34 1/4 ?

Any help is appreciated...

Montalaar
07-16-2010, 08:35 AM
If your ATA is 2" off there is something major wrong. Decreasing the ATA around 1" can lead to limb problems with the CAT-Cams. The ATA measurement might be something mroe or less approximate but your ATA is way off.

Did your shop sell you the bow with the ATA this way off? Get this straigthend out! Either the string is way short (which will rotate the cam forward) or the cables are way short (also will rotate the cam forward) or both are way off (will not rotate the cam). Anyway: THis has to be corrected!

kylebattell
07-16-2010, 09:01 AM
Whoops ! My Axle to Axle is actually 32 3/4...so its a 1/2 inch...Sorry for the typo!

kylebattell
07-16-2010, 09:03 AM
This is the Firecat TR2 Axle Length: 32 1/4 so i'm a 1/2" off...

Montalaar
07-16-2010, 09:27 AM
Okay. In this case it is within a range that is acceptable. You may want to try to minimize the difference between your ATA and the original specs.

Have you finetuned your CAT-Cam? I do not believe that there is something like a 'sweet spot' but there might be something similar. A certain position where the cam rotation will lead to a maximum performance within its limits.

kylebattell
07-16-2010, 09:45 AM
Would adjusting the "draw stop" potentially find the cams right spot ?

Montalaar
07-16-2010, 09:59 AM
No. It might be necessary to do some cable or string twisting. This will change the Cam orientation and rotation.



Twisting Cables:
Retards Cam, Increases DL, Increases DW, Decreases ATA, Increases BH.

Untwisting Cables:
Advances Cam, Decreases DL, Decreases DW, Increases ATA, Decreases BH.

Twisting String:
Advances Cam, Decreases DL, Decreases DW, Decreases ATA, Increases BH.

Untwisting String:
Retards Cam, Increases DL, Increases DW, Increases ATA, Decreases BH.

Tightening Limb Bolt:
Advances Cam, Decreases DL, Increases DW, Increases ATA, Decreases BH.

Loosening Limb Bolt:
Retards Cam, Increases DL, Decreases DW, Decreases ATA, Increases BH.
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For further information you can also go to www.archerytalk.com/vb/ and search for CAT cam tuning.

kylebattell
07-16-2010, 10:08 AM
Thank you for your help

Destroyer
07-16-2010, 07:29 PM
ABO speed

Whats ABO?

bfisher
07-17-2010, 09:05 AM
Whats ABO?

Thankyou for asking. You beat me to it. It's a term I have never heard before. And in 37 years I thought I had heard them all.

Aaaaah, I'll bet he means AMO. The old speed rating back in the 80's and early 90's. If I remember right it was at 30", 60#, and shooting a 540 grain arrow (9 gr/lb).

Destroyer
07-17-2010, 11:05 PM
Aaaaah, I'll bet he means AMO. The old speed rating back in the 80's and early 90's. If I remember right it was at 30", 60#, and shooting a 540 grain arrow (9 gr/lb).

AMO hey, hmmmm......the real speed rating. :p

bfisher
07-18-2010, 07:05 PM
AMO hey, hmmmm......the real speed rating. :p

Not really. I don't know anybody who shoots 9 gr/lb any more. There are certainly a few, but I don't know anybody. Tell ya one thing though. It sure makes for a nice quiet hunting bow and a lot less damaged limbs.

Still, when bows were shown with both AMO and IBO ratings I used to just split the difference for what I figured a bow would get and this came out closer in the real world than the inflated number advertised today.

Frankly I get such as kick out of all the pseed talk these days. Guys think bows are so much faster than just 5 years ago. I had a bow once that shot 50#, 27" draw, and the arrow was an X7 1614 weighing 281 grains. It shot that arrow at 232 fps, not blistering by today's standards, but this was a 1977 Jennings Arrowstar with round wheels, 40% letoff, and Dacron string.

I also had a 1979 Pearson Prostaff 4000 (61#, 28" draw) that shot a 540 gr XX75 2018 at 228 fps. This was a hunting setup. It peaked 61# with 38# holding weight. Try that on for size today.

I had a 1992 Darton Viper that shot 281 fps at 6 gr/lb. If I recall correctly this one had an AMO speed rating of 235 fps.

So really, bows today are not all that much faster considering the technology that has gone into the cams and reflexed risers. All the risers did was eliminate the use of overdraws. Now it's built in. Bows today have no resemblence to those of yesteryear except that they have a riser, two limbs, some wheels, and string/cables holding it all together. That's one thing that hasn't really changed at all.

Destroyer
07-19-2010, 09:12 PM
One thing that has changed it the perception of what a speed bow is. Today a 7" brace height is forgiving!