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flag Petiloi
O+
Posted: Jun 16, 2021 at 15:03 Quote
matarratas wrote:
Hello everyone,

Does anyone on this forum have a Size1 of the NV145, or the NV170?
Thanks

I have a NV170 size 1. Are there any questions I can answer?
flag jgottya1
Posted: Jun 16, 2021 at 17:33 Quote
matarratas wrote:
Hello everyone,

Does anyone on this forum have a Size1 of the NV145, or the NV170?
Thanks

Hey there,
Sorry i do not. Mine is a size 2 NV170
flag jgottya1
Posted: Jun 16, 2021 at 18:10 Quote
LesZedCB wrote:
how often are you all on air shocks bottoming out? are you running max spacers?
Not on air even though i ordered the frame with the T3 but sold it and put a DVO jade on it and currently settled on a linear spring. With the independant high and low compression adjustments It works absolutlety incredible. No harsh bottoms out on sizable drops to flat (4-7 feet) and the rear suspension feel is incredible with this shock(incredible like DH plush without sagging 50% of the stroke). I started with a progressive spring and ditched that shortly after. Mid stroke support on the jade is fantastic.
Any good shock with indy hi/lo should make it work well, depends on if you want more progressiveness from air spring.
flag matarratas
Posted: Jun 21, 2021 at 10:00 Quote
Can anyone measure the effective top tube of a size 1, NV145 or a NV170 please?
Thanks
flag matarratas
Posted: Jun 21, 2021 at 12:02 Quote
As a matter of fact, can anyone verify the Values on the Geometry Charts provided on their website with your bike? No matter what size or model you have.
Thanks
flag jgottya1
Posted: Jun 21, 2021 at 18:58 Quote
matarratas wrote:
As a matter of fact, can anyone verify the Values on the Geometry Charts provided on their website with your bike? No matter what size or model you have.
Thanks

Yeah i will measure my 2 in an hour or so when i am done with work.
flag jgottya1
Posted: Jun 21, 2021 at 22:32 Quote
matarratas wrote:
As a matter of fact, can anyone verify the Values on the Geometry Charts provided on their website with your bike? No matter what size or model you have.
Thanks

So on the 2..
With 27.5 wheels front and rear, 180 mm travel fork...63.5 headtube angle
Effective top tube length measured horizontally from center of headtube to center of seatpost 597 mm
Seat tube length from center of bottom bracket to top of seat tube 457.2 mm
Chainstay and headtube length are same as listing on site.

I am not sure how they measure if ctr to ctr, ctr to outer/ inner or outer to outer or inner to inner. I always go ctr to ctr other than seatube length goes ctr of bb to top of top tube (unless it extends past the top tube, then ctr to ctr)
flag matarratas
Posted: Jun 22, 2021 at 6:54 Quote
Thanks for checking this. I went back to take a look at your bike, you did a great job with it!!

From your measurements, im surprised how much difference there is with the values provided.

im a mess right now trying to figure out if this will work for me or what!

Dead Horse
flag jgottya1
Posted: Jun 22, 2021 at 11:59 Quote
matarratas wrote:
Thanks for checking this. I went back to take a look at your bike, you did a great job with it!!

From your measurements, im surprised how much difference there is with the values provided.

im a mess right now trying to figure out if this will work for me or what!

Dead Horse
No prob. Thanks man. Has a few changes since. Some green spank bars and crank brothers / industry 9 synthesis wheels and an e13 bash/chain guide. Dealing with 3 broken ribs and slight bicep tear from my first DH trip post covid so it will be a bit before I can enjoy this thing.

Yeah on the #s, not sure how he measures to listing. Best bet would be to email Matt. The bike is sweet rig for a custom build at not an obnoxious price. Hopefully it will work for you.
flag MegalodonMatt
O+
Posted: Jun 22, 2021 at 13:31 Quote
matarratas wrote:
Can anyone measure the effective top tube of a size 1, NV145 or a NV170 please?
Thanks

I just checked some of the measurements on my size 2 LV145. 29 front and rear with a 160mm fork...

Seat tube was 427mm from center of the intersecting tube to the top of the seat collar. Came in at about 460mm when measured from the center of the cranks. (Listed as 425mm) I still fit a 200mm dropper on it though and I'm 5'10", which is on the small end for a size 2 frame, so no complaints here.

Actual top tube I had at 621mm center to center. Effective, I got 602mm (Actual listed at ~626mm)

Not sure how to measure a chainstay, but from axle center to linkage bolt center was about 472mm in the shortest setting. Says it should be between 445-460mm for all sizes, so maybe I'm doing that wrong..

Edit: After remeasuring both the seatstay and head tube angle, they were spot on at 76* and 64*!

Hope that helps.
flag matarratas
Posted: Jun 22, 2021 at 17:05 Quote
MegalodonMatt wrote:
matarratas wrote:
Can anyone measure the effective top tube of a size 1, NV145 or a NV170 please?
Thanks

I just checked some of the measurements on my size 2 LV145. 29 front and rear with a 160mm fork...

Seat tube was 427mm from center of the intersecting tube to the top of the seat collar. Came in at about 460mm when measured from the center of the cranks. (Listed as 425mm) I still fit a 200mm dropper on it though and I'm 5'10", which is on the small end for a size 2 frame, so no complaints here.

Actual top tube I had at 621mm center to center. Effective, I got 602mm (Actual listed at ~626mm)

Not sure how to measure a chainstay, but from axle center to linkage bolt center was about 472mm in the shortest setting. Says it should be between 445-460mm for all sizes, so maybe I'm doing that wrong..

Seat tube angle was a spot on 76*, but oddly enough my head tube angle came in at 66*(supposed to be 64*)..but in fairness I was using a free iPhone app with a case on it, so I'm not expecting perfection.

Hope that helps.

This is all very interesting, guys.

How do we process all this..

- Seat tube length should be measured from center of BB to top of the tube (I would). Therefore I'll take your 460mm length (Sample 1), and the other 457mm length measured by jgottya1 (Sample 2). The chart shows 425mm for both models (interestingly close to when measuring from the top of the tube to the intersection with... the first tube it intersects).

- The Effective Top Tube measures 602 on sample 1, and 597 on sample 2. The chart claims an "Effective Top Tube (approx) 626mm, which as you mention it is much closer to the Actual Top Tube measurement, at 621 on Sample 1.

- The Chainstay Length should be measured from the center of the BB to the center of the wheel axle. This is why at this point the measurement from Sample 1 is most likely rejectable. Sample 2 is a N/A.

- Seat Tube Angle also has an Effective and an Actual value. I assume you may have taken the Actual, because it is easier to measure. I think an effective would give me a better idea of the bike fit, and then additionally the actual would let me know what happens when the seat is above the "effective line" (will the distance btw the seat and the steer tube grow or shrink?).

- Head Tube Angle: whoa that one is a bit of a mystery. The difference btween sample 1 and the chart is really big. If I could choose tho, I think Id rather be closer to 66, than 64 degrees, but I will agree with you that your measuring tool has some limitations.

My first conclusion for all this is that the geometry chart is far from accurate. Maybe that's what "progressive forward thinking geometry" means lol

I guess it boils down to sitting on the actual bike. Is there anyone in the Seattle area that would let me sit on their ferrum size 1 or size 2?
flag jgottya1
Posted: Jun 23, 2021 at 7:01 Quote
Machinist protractor on seat tube of NV170 with 180 mm fork shortest dropout position and dual 27.5 wheels

Ok so machinist protractor puts my seatube at 77.25 (further back here you can see my ht with same device)
Seat stay ctr B.B. to ctr wheel axle, 444.5 mm
Actual top tube length, ctr headtube to ctr of seat tube, 609.6 mm
Seat tube length from ctr of B.B. to ctr of the first intersecting tube(the top tube) 342.9 mm

Sorry I am on the opposite side of the country, but you are more than welcome if you are in the Northeast any time.

Also.. 425 mm seat tube listed puts it spot on when measuring from ctr of B.B. to top of the short gusset tube that connects the seattube to the top tube. I got about 425.2.
flag matarratas
Posted: Jun 24, 2021 at 12:37 Quote
jgottya1 wrote:
Machinist protractor on seat tube of NV170 with 180 mm fork shortest dropout position and dual 27.5 wheels

Ok so machinist protractor puts my seatube at 77.25 (further back here you can see my ht with same device)
Seat stay ctr B.B. to ctr wheel axle, 444.5 mm
Actual top tube length, ctr headtube to ctr of seat tube, 609.6 mm
Seat tube length from ctr of B.B. to ctr of the first intersecting tube(the top tube) 342.9 mm

Sorry I am on the opposite side of the country, but you are more than welcome if you are in the Northeast any time.

Also.. 425 mm seat tube listed puts it spot on when measuring from ctr of B.B. to top of the short gusset tube that connects the seattube to the top tube. I got about 425.2.

Heh, thanks for the offer. Ill try to find some Ferrums on my neck of the woods tho. And thanks for measuring!
flag jgottya1
Posted: Jun 24, 2021 at 22:55 Quote
You’re welcome. Hope you can get where you need to be with one. Good luck!
flag LesZedCB
Posted: Jul 14, 2021 at 13:06 Quote
well, finally received my frame yesterday (ordered end of march) and finished the build today. came in at 37lbs flat with the following spec:

NV 170 29er:
Rockshox Lyrik Ultimate 170
DVO Topaz T3 Air
GX Eagle cranks, chain, shifter, cassette, NX derailleur
Hunt Enduro Wide 29er Wheelset with Specialized Butcher 2.3 blck dmnd casing, tubeless
Magura MT5 brakes, 203 front/rear
SDG Tellis 170mm dropper
Crankbros Mallet E pedals
Deity Topside Alu bars
Spank Spoon stem 45mm
Fabric Silicone Grips

photo

 


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