Mountain Bike Reviews Forum banner

1 - 20 of 140 Posts

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #1 ·
I have a RS Monarch Plus 7.5x2 lying around from my previous bike, which I want to try on my Phantom.
I have a set of offset bushings on the way, with a total of 3mm offset (2+1mm).
With 0 compression the eye2eye will be 3.35mm (1/4" - 3mm) longer than today, and with full compression the fully compressed shock will be 3mm shorter than today.
I've checked frame clearance which seems ok.
If the leverage ratio can be assumed constant, the travel will be 105 x (2/1.75) = 120mm.


Any reason not to do this?

How will the suspension work in the 3mm/3.35mm "outside" each end of the current stroke?
 

·
Registered
Joined
·
24,083 Posts
Absolutely no clue, although I did query Keith on using just the longer shock and he said it wouldn't be good. If it were me personally, since you've got the shock and already ordered the bushings, I'd give it a go and get the answer for myself. You've actually got 2 problems, one being that the shock will take the kinematics outside their designed intent and two the shock may not be tuned to suit the KS link. Please report back if you try it.
 

·
Registered
Joined
·
1,423 Posts
Banshee Phantom 29'' 2014 - Linkage Design

This can give you some idea once you start to understand how to read the info. The way you are doing this is just adding a bit to each end of the travel and I don't see that you will notice much as far as a negative. If you use 30% sag as a constant you will be sitting at almost the same spot with the longer shock/ bushing combo when compared to the shorter stock shock. Thus, pedaling response should be the same as stock.

I was just contemplating this exact possibility last week so I'm very interested in your journey. I'd be interested in a 120 rear/ 130 front Phantom...

Please post specifics on the bushings you ordered. How does one bushing give more offset vs the other? Both bolts are 8mm so I'm not following why both aren't the same offset.

What is the compression/ rebound tune on the stock Monarch for the new Phantom?

Most every bike designer/ company is going to say this is a bad idea...if for no other reason than legal implications.

Have fun!
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #4 ·
Banshee Phantom 29'' 2014 - Linkage Design

This can give you some idea once you start to understand how to read the info. The way you are doing this is just adding a bit to each end of the travel and I don't see that you will notice much as far as a negative. If you use 30% sag as a constant you will be sitting at almost the same spot with the longer shock/ bushing combo when compared to the shorter stock shock. Thus, pedaling response should be the same as stock.
^^This is what I'm thinking as well. How bad can it possibly get??
Also, I think I have to learn some spanish..

Please post specifics on the bushings you ordered. How does one bushing give more offset vs the other? Both bolts are 8mm so I'm not following why both aren't the same offset.
Ordered from these guys:
https://www.offsetbushings.com/collections/frontpage/products/offset-bushings-pair

With an 8mm bolt the max offset per bushing is 2mm, so I specified 2+1mm.

What is the compression/ rebound tune on the stock Monarch for the new Phantom?
Don't know, but the shock I'm gonna use is M/M
 

·
Registered
Joined
·
24,083 Posts
From all the reports and responses I've read from Banshee, on RS stuff, that's the tune you want. Curious if you also have the spec'd 184x44 shock and have or will try that so you can have a true appreciation for your "mod"?
Don't know, but the shock I'm gonna use is M/M
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #6 ·
That's good to hear!

The bike came with the DB Inline shock, so it wont be a 100% comparison.
 

·
Registered
Joined
·
1,423 Posts
Lol...I don't know Spanish either. I just know how to use Google Translate! Even then I have to read it slow and make sure I know what he's saying. I really like all the work that guy has done to help us compare different bikes and platforms kinematically.
 

·
Here, diagonally!
Joined
·
2,097 Posts
Sounds doable with the offset bushings. Keep going with the modifications, and pretty soon you'll have a Prime. :)

I shouldn't even mention this, but I've considered long-shocking my Prime to 150mm travel. 8.5 x 2.5 shock. I've measured it out in detail several times. Unfortunately, it involves drilling a new shock mount hole in the frame, and trimming the mount so the original hole is never usable again. XL is probably the only size with enough meat on the mount to do this. The devil is tapping me on the shoulder, but I've been wise enough not to do it....so far.
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #9 ·
Sounds doable with the offset bushings. Keep going with the modifications, and pretty soon you'll have a Prime
Haha :)

I was actually more keen on a Prime, but since I couldn't find one in the correct size I had to go with a Phantom.
Can't say I regret though :D
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #11 ·
Bushings in da house..

..BUT the front bushing is 5.4 mm too narrow (2017 vs 2016 frame), so I still have to wait some more to test the setup on the trails.

I still managed to check the shock length in a compressed and extended state, and it seems like a total offset of 4mm (I have 3 now) is well within the range of motion of the rear triangle.

So I'll buy one more bushing with 2mm offset, to be able to run both 3mm(2+1) and 4mm(2+2) total offset.

The waiting continues..
 

·
Registered
Joined
·
67 Posts
I have a RS Monarch Plus 7.5x2 lying around from my previous bike, which I want to try on my Phantom.
I have a set of offset bushings on the way, with a total of 3mm offset (2+1mm).
With 0 compression the eye2eye will be 3.35mm (1/4" - 3mm) longer than today, and with full compression the fully compressed shock will be 3mm shorter than today.
I've checked frame clearance which seems ok.
If the leverage ratio can be assumed constant, the travel will be 105 x (2/1.75) = 120mm.


Any reason not to do this?

How will the suspension work in the 3mm/3.35mm "outside" each end of the current stroke?
i've used offset bushings in the past to get lower BB and steeper head angle,
all in all, it is a cheap and effective hack but you can now get 185X50 Metric rear shocks which should fit without bushings

​The Ultimate Guide to 'Metric' Shock Sizing and the RockShox Super Deluxe - Mountain Bikes Feature Stories - Vital MTB
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #15 ·
i've used offset bushings in the past to get lower BB and steeper head angle,
all in all, it is a cheap and effective hack but you can now get 185X50 Metric rear shocks which should fit without bushings

​The Ultimate Guide to 'Metric' Shock Sizing and the RockShox Super Deluxe - Mountain Bikes Feature Stories - Vital MTB
The new shocks look interesting, but my idea now is to see if I can use my old shock without spending too much money.
(Also good to have a backup shock if/when the CCDB IL dies..)
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #17 ·
Back again with an update:

My original estimates wrt how much offset I could use were a bit conservative, so I've ended up with 2mm on each bushing, 4mm total. This is well within the range of motion of the rear triangle.

The two pics attached (are meant to) show the distance between seat tube and tire, and between seat stay bridge and sest tube. Both taken at full compression.
Tire is Minion DHR2 2.4 on a 32mm inner rim, with 650b dropouts in slackest setting.
Sorry about the 90degree error..

I haven't done any back to back testing against the original CCDB Inline so I can't come up with a list of pros and cons, but I can say it doesn't feel totally wrong :)
 

Attachments

·
Registered
Joined
·
24,083 Posts
So curious, looks like you have loads of room, why the 650B/long drop outs? Still very interested to hear how it rides.
langen said:
Both taken at full compression. Tire is Minion DHR2 2.4 on a 32mm inner rim, with 650b dropouts in slackest setting.
 

·
Bigger is better!
Joined
·
725 Posts
Discussion Starter · #20 ·
So curious, looks like you have loads of room, why the 650B/long drop outs? Still very interested to hear how it rides.
I'm 6'9" with a 42" inseam (with ditto high seat), so I want the rear wheel as far back as possible for not un-weighing the front wheel on climbs.
 
1 - 20 of 140 Posts
Top