Carbonda fm936 Thoughts

[theirishrider]

is to model the frame in a CAD program.

One day im going to do that.... But dont hold your breath

I'm trying to draw it up in CAD but I don't have enough dimensions to draw it. I need:

• The length from the rear axle to the joint between seat stay amd rocker link.
• the dimensions of the shock, chainstay and pivot frame linkage all relative to the BB

If someone gives me this, I can put it on CAD

[zilcho]

is to model the frame in a CAD program.

One day im going to do that.... But dont hold your breath

I'm trying to draw it up in CAD but I don't have enough dimensions to draw it. I need:

• The length from the rear axle to the joint between seat stay amd rocker link.
• the dimensions of the shock, chainstay and pivot frame linkage all relative to the BB

If someone gives me this, I can put it on CAD

Let me know if that helps or if I need to measure anything else.

[theirishrider]

Let me know if that helps or if I need to measure anything else.

Perfect!! I should have explained better, I need the vertical offset (bit of trig) of these points relative to the centre of the BB:

• the lower shock bolt
• chain stay frame bolt
• frame rocker bolt
• [EDIT] no horizontal offset just the distances between the bolts on the rocker linkage

Completely understand if thats too much effort but i dont have my frame yet

[zilcho]

Let me know if that helps or if I need to measure anything else.

Perfect!! I should have explained better, I need the vertical offset (bit of trig) of these points relative to the centre of the BB:

• the lower shock bolt
• chain stay frame bolt
• frame rocker bolt
• [EDIT] no horizontal offset just the distances between the bolts on the rocker linkage

Completely understand if thats too much effort but i dont have my frame yet

lower shock bolt: 8cm
chain stay frame bolt: 6.5cm
frame rocker bolt: 22.5cm

linkage:
shock to frame bolt: 4.8cm
frame bolt to seat stay: 6.2cm
shock to seat stay: 8.8cm

They might be off by a couple of millimetres

[theirishrider]

Given it a crack but im over 1cm off on the shock size so there's too much error accumalation. When I get my frame I'll measure it up anbd put my engineering degree to good use ahahah Thanks to zilcho for giving it a go however!

[carbonazza]

I got poor results too when drawing something from the geometry file from Carbonda's web site + zilcho's measurements.

Scaling it properly to have the chainstay length correct, the shock length is almost good too. If someone had the courage to measure the A, B, C, D maybe the result would be better.

Some other dimensions are off, like if the drawing was between an S and a M.
But then I realized there must be some sag changing the initial 165mm, not sure how much this represent... compared to the travel 



Too late to make any change anyway, r2-bike.com shipped the SIDLuxe 165x42.5 shock today !! 

[zilcho]

My measurements before were to the BB.  Assuming that ABCD are to the chain stay pivot, this is what I measured

A: 45.8
B: 43.2
C: 18.7
D: 20.2

165x42.5 has had zero issues for me so far, would be nice to see the numbers though

[Colt__Seavers]

Got me a 165x42,5 Fox Factory Float DPS EVOL. I normally wanted to have a 165x40, but the 42,5 was only 100€ new.
Hopefully I can run it together with a 100 SID Ultimate RD.
Any problems which might occur?
Using an XL frame. Carbonda recommended a 40mm

[Vipassana]

Here are the wheels I am considering:

Carbon - https://www.lightbicycle.com/Hand-built-All-Mountain-Cross-country-carbon-29er-MTB-wheelset-30mm-wide-tubeless-compatible.html
AL - https://www.lamacycles.com/en/ns-bikes-octane-one/wheels-wheelsets/29-wheelsets/ns-wheelset-enigma-lite-29

I was going to go with the hunts new xc rim but they aren't in stock until the end of October.

Really stuck on how to save weight on a budget with the brakes and groupset.

Any recommendations for light weight groupset/brakes

Why not buy carbon wheels ? AM wheels are as strong if not stronger than aluminium, and come with this light feeling you get each time you accelerate.
You can get very good wheels from 500 to 900USD depending on the hubs and spokes you choose.

I make a lot of mistakes riding and carbon rims seems a bit more delicate. I'm hoping to get a very long life from aluminum rims.

In my experience, carbon rims of similar weight and widths are quite a bit more durable than their aluminum counterparts.  They are also a LOT stiffer laterally and increase steering precision IMO.  They also, stay truer longer in my experience.

Been 100% on carbon on the MTB for well over a decade now and I've managed to break only one superlight XC 29er rim (305 grams) - that rim strike would have ruined an aluminum rim too (high speed, extremely low tire pressure).  I ride lots of rocky stuff here on the east coast and my rims def get a beating and scarred up. 

I was leery at first as well, just start with a heavier duty rim to gain confidence in them - something in the 425-450 range for XC will be plenty tough.  If I was limited to one carbon item on a bike it would be rims 1st for me.   

When it comes to weight savings, spend the money to have it on the wheels.  That's two fold benefit, static and rotational gains.

For brakes, don't over think it. Pick up some SLX or XT. Very affordable, very robust, decently light. I'd wager there's no better all-around brakes than a set of XTs with ICEtech rotors and pads. You could go 180mm or 4 piston if you need more breaking power, but I don't think you will.

[tripleDot]

Just passing thru to read a bit. I'm now reminded of why I simply went full rigid. FS just became as complicated as advance mathematics.

[carbonazza]

My measurements before were to the BB.  Assuming that ABCD are to the chain stay pivot, this is what I measured

A: 45.8
B: 43.2
C: 18.7
D: 20.2

165x42.5 has had zero issues for me so far, would be nice to see the numbers though

I get again some stupid results.
Probably my assumption of having a 165mm shock when mounted is wrong.
Or maybe something else.

Could you get the E and F measurement, last try 


The SIDLuxe arrived much quicker than I expected, the frame and wheels are still being built...


And here is a very friendly video, ok marketing too, but full of details about the new SID:

A fun fact: It seems locking the fork/shock is a European thing 

[theirishrider]

Just the quote from Carbonda. Question about shipping, has anyone gone with the train option? haha might take a while but the savings are considerable.
From Adam (v helpful guy):

• shipping to The Republic of Ireland: 1,by train,90USD,shipping time 30-45 days,2,by XDB,185USD,shipping time 20-35 days.3,by DHL,220USD,shipping time one week.  which do you prefer?

[adbl]

I have a hard time of trusting any of the Chiner geometry drawings. Not because they are trying to deceive or are just getting it wrong. These open mold frames go through so many iterations that the one we see posted might not be the final iteration or at least the drawing is not updated to the most current geo numbers.

Having said that, you need to at least have a starting point to begin with. Without having a frame here in front of me to measure I have no choice but to reference the drawing. If I were to assume the drawing as listed on their site is accurate at 100mm travel, then according to my calculations shock travels would be as follows:

40mm shock = 101mm travel
42.5mm shock = 105mm travel
45mm shock = 112mm travel

My calculations come from a CAD program that has been used in Motorsports for years to model suspension kinematics and is dead nuts on!

[zilcho]

My measurements before were to the BB.  Assuming that ABCD are to the chain stay pivot, this is what I measured

A: 45.8
B: 43.2
C: 18.7
D: 20.2

165x42.5 has had zero issues for me so far, would be nice to see the numbers though

I get again some stupid results.
Probably my assumption of having a 165mm shock when mounted is wrong.
Or maybe something else.

Could you get the E and F measurement, last try 


The SIDLuxe arrived much quicker than I expected, the frame and wheels are still being built...


And here is a very friendly video, ok marketing too, but full of details about the new SID:

A fun fact: It seems locking the fork/shock is a European thing 

E: 5.7
F: 16.3

[zilcho]

I have a hard time of trusting any of the Chiner geometry drawings. Not because they are trying to deceive or are just getting it wrong. These open mold frames go through so many iterations that the one we see posted might not be the final iteration or at least the drawing is not updated to the most current geo numbers.

Having said that, you need to at least have a starting point to begin with. Without having a frame here in front of me to measure I have no choice but to reference the drawing. If I were to assume the drawing as listed on their site is accurate at 100mm travel, then according to my calculations shock travels would be as follows:

40mm shock = 101mm travel
42.5mm shock = 105mm travel
45mm shock = 112mm travel

My calculations come from a CAD program that has been used in Motorsports for years to model suspension kinematics and is dead nuts on!

Could you model the NS frame dimensions as well?  Curious how it stacks up b/c the rear triangle measurements look the same to me, just visually different.