Current shock is Monarch 200 X 57, the min clearance for the frame with shock fully compressed is 142mm, so could I take a risk at 184X44 & if it hits get a smaller than the current 2.35 fat Albert tyre to give me the extra couple of mm, or does it not work like that?
Could I have my current shock reduced so that I lose 20mm from the stroke & reduce the travel of the bike? It’s currently 150mm rear travel, anything north of 100mm will suffice, anyone care to explain the math?

Cheers.

I know with Fox shocks you can reduce the stroke on a 200×57 to 200×51 using a reducer (which has to be fitted during a service i think) which would reduce the travel by roughly 18-20mm so it’s probably possible with a Rockshox shock,
As for lowering the bb maybe some offset bushes would work but it’d change the angles as well..
A 190×50 Shock might do both as long as there’s enough clearance under full travel

The maths not that simple as it depends on the linkage leverage ratio.
Take a look at what Scott did with the first generation voltage fr for adjusting shock i2i and consequently travel and geometry.
You can depressurise/sag in your existing shock to see what it looks like as a 184mm i2i and how low it send your BB right off the bat.

If you shorten the shock, the seat tube angle will be slackened, which will have an adverse effect on the bikes climbing ability

Would raising the pressure (to effectively limit the travel cos you’d have to run a shorter travel shock at higher pressure anyway with the linkage on your bike) and some offset bushings (to lower the BB) do the same job?

Put on 5 stone, should do it.

I found a cheap fox vanilla shock on eBay so I have bought it to test out the geo, I’ll decide based on that.
Cheers.

Let all the air out of your back tyre

To get your overall leverage ratio, divide the travel (150mm) by the shock stroke (57mm) which gives you

150/57 = 2.63

So, to work out how much travel you’ll have for a given shock stroke, times the stroke (44mm) by the leverage ratio

44×2.63 = 116mm

However, loosing that much Eye to Eye on the shock is likely to makes things crazy slack and lower your BB excessively… Offset Bushes normally only lose about 6mm Eye to Eye, so 16mm could slacken your bike by more than 2 degrees on both the head and seat angles.

I’d say you’d be better trying out a 190×50 shock, but it sounds like you’ve already bought the replacement shock… Let us know how it works out.

jivehoneyjive,

I’m so sorry that I didn’t see & thank you for your’e very informative post, so here’s a belated thank you from me

The shock I bought didn’t work out due to the seller measuring end to end & not i2i 👿

I have bought another & I’ll update in due course.

Cheers.