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Making sense of the ‘19 GT Sensor 29

43K views 233 replies 39 participants last post by  SergMTB  
#1 ·
The new Sensor has good value, good initial reviews and seems to fit in perfectly next to other exciting new short travel 29ers like the SBG Transition Smuggler. Except for one important geo figure: bb height. Even in the low geo setting the Sensor bb is about 17mm higher than the Smuggler. This might be a welcome change for some with really rocky climbs or tall people who need to run 175mm cranks. It’s also a golden opportunity for those who like to experiment with wheel sizes, specifically mixed wheels sizes: 29 front 27.5 rear. I have played around with the reverse mullet a bit and really really liked it. You get the incredible 29er stability and traction you need through the bars and front end, but the snappy, playful rear 27.5ers are know for.

I started this thread hoping to get some input from knowledgeable ppl on this idea and maybe to inspire some others to try it. Correct me if I’m wrong: the overall wheel diameter difference between 29 and 27.5 is 38mm when running the same tires. If you run a 27.5+ that number goes down a bit. So you’re looking at a 19mm drop in the rear axle height, which will net about 10mm drop in bb height and -1 degree slackening of the hta and sta. The seat can be slid forward to help counteract the slacker sta, making the tt length a bit shorter.

Reverse mullet GT Sensor geo changes:
64.5 hta
75 sta
346 bb height

Sounds like a pretty incredible trail bike to me. I’m in the market for a bike like this and just might pull the trigger when frame sets become available next month.
 
#194 ·
Fork offset/travel question?

This is related to a '20 model frame with a RS piggyback shock that was spec'd using a 140 44 offset fork on the full build, the previous model had a 51 os fork I believe.

My question is if one was to run a 150 fork on it but with a 51 offsethow would that affect handling characteristics? Reason being I had purchased a fork for a different frame designed on a 51 offset that came damaged and the vendor has no more frames available to replace in like kind.

Thanks in advance.
 
#228 ·
Fork offset/travel question?

This is related to a '20 model frame with a RS piggyback shock that was spec'd using a 140 44 offset fork on the full build, the previous model had a 51 os fork I believe.

My question is if one was to run a 150 fork on it but with a 51 offsethow would that affect handling characteristics? Reason being I had purchased a fork for a different frame designed on a 51 offset that came damaged and the vendor has no more frames available to replace in like kind.

Thanks in advance.
Just put a 140mm RS Revelation RC (44mm offset) on the front of my 2019 Sensor Comp which came with a 130mm RS Sektor (51mm offset). The 140mm RS Revelation RC has the Pike's beefier chassis, and I've noticed the front end feels a good bit more stout when plowing into tight corners at speed. I haven't noticed any unusual changes in the handling thus far. Overall, it's a nice improvement, and I do like the slightly bit more of upright riding posture afforded by the slightly taller front end. One benefit is that I can use a 180mm rotor without an adapter for even better brake feel....
 
#202 ·
Update

Got a set of brakes.? Got build done last night up to the dropper post then realized I had a 30.9 post, needed a 31.6! Ugh. Got a sp reducer shim today. Thought all was good. Then realized I needed an adapter barrel to accept the small head of the dropper cable slot to the dropper actuator thangy. Another ugh...hope to round up tomorrow...

Anyway, coming from some more xc type setups, surprised by the weight of this frame setup with the DPX piggyback shock thang and all that this might be considered more of an "all mtn" type rig even though it's a 130/140(possibly 150 fork if so desired?)setup. I imagine with the right tyres and suspension setup an aggressive "lightweight" rider such as myself could tackle some descent routes given that some DH guy with "skillz" named "Phil" has moved onto one of these from his 27.5 Force!

Looking forward to putting this thing to the test on some dirt over the weekend!
 
#204 ·
First break-in outing

Sure is purdee in the sun. So glad it isn't the burnt pumpkin colour on the '19.

Rear suspension felt pretty composed more so than my V1 Ripley to a point I could easily see switcing the 140 34 Perf Elite over to a 36. Still have to do some adjusting on shock as I've never had a piggyback reservoir type.

Build came in at ~31#'s was hoping the weight would've been sub 30 as it's a small frame with e13 carbon cranks, TRS race alloy wheels, Vittoria Martello/Aguarro tires, xx1/xo1 drivetrain and xtr trail pedals. Only thing to upgrade with max investment minimal gains would be carbon wheels(-~50 grams over the alloy) and bars.
 

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#208 ·
Love the Red, its hot! Looks awesome JR13!
So i am trying with putting on a 185x55 shock. Someone earlier said it would fit but did not mention travel. Im guessing 140mm perhaps. Im also thinking about testing a 150mm fork. Im hoping to give an enduro race a try next season and the Sensor is the weapon of choice or its all i have lol 🙂