So, you are thinking of going to shorter cranks. here's what i think.

[ACyclingRooster]

Hi again to you all. A little bit of history on my choice of crank length and other topical factors.
When I first started with a serious steed at 16 years of age and it was a pre-owned 1937 19& a half inch Hetchins Vibrant Triangle (19.5 cm) 2 day Brilliant that had allegedly been used at Herne Hill - NO Badges or frame ID except the obvious one of the rear stays !!

Frame number H108 stamped on the underside of the BB shell and on the track drop-outs.

I road that frame for many many years with 170mm crank arms pushing a 108" fixed gear and a rather unusual pair of "French style" dropped bars and the obligatory single front brake.
I developed calf and thigh muscles like "Mr Universe" conducting my daily 8+ miles morning ride into Liverpool and back home at night.
I rode in all weathers including the rain,snow,fog and the infamous Smog of the day.

My treasured Hetchins was stolen by some light fingered individual and ended up being stripped of the double crown forks and hung up for sale in what was then The Liverpool Cycle Exchange in the town centre.

I got the frame back minus the forks and rebuilt the bike after the track ends were removed and replaced with road drop-outs as a road bike with a five spd derailleur gear and twin chain-rings and front and rear brakes.

The Hetchins was eventually/foolishly sold when I got married on 25th March of 1967 because of a lack of somewhere to keep it.

 

[bkatelis]

Selling cherished bikes, a poignant farewell for cyclists. Yet, it's not just about the bike, but the journeys and memories that give it soul. The cycling community often refers to this as "bike separation anxiety." It's a reminder of the profound impact cycling has on our lives, shaping our experiences and identity. So, as you bid farewell to your trusted steeds, remember the adventures they've brought you and the ones yet to come. #bikecommuinity #cyclinglife #bikeseparationanxiety

 

[ACyclingRooster]

Hi again to you all. A little bit of history on my choice of crank length and other topical factors. When I first started with a serious steed at 16 years of age and it was a pre-owned 1937 19& a half inch Hetchins Vibrant Triangle - Curly - (19.5 cm) but unfortunately that was stolen from my then place of work in Liverpool.
The frame minus the double crown forks turned up several months later at the Liverpool Cycle Exchange hanging on the wall behind the service counter.

After a length conversation and showing evidence that it was my frame it was returned after I mentioned bringing in the police !!

The bike was later rebuilt with a Chromed front fork and a 5spd derailleur after the track ends were removed and replaced with road dropouts and the rear stays made a little wider so that the 5spd Regina block could be accommodated and twin TA chain-rings with 175mm cranks.

I kept the bike until I got married on 25th March 1967 and then it was sold to Harry Hall Cycles in Manchester.

 

[bkatelis]

Alright, let's cut to the chase. I see you've got a history with your bikes, but let's not get too sentimental here. You mentioned your Hetchins Vibrant Triangle with 175mm cranks. Sure, it's a classic, but let's talk performance. Longer cranks might give you a bigger lever, but they also mean more strain on your knees, especially post-surgery.

You're not 16 anymore, and your body's not the same. You've got to adapt to the changes. Consider shorter cranks, like 170-172.5mm. They'll reduce the strain on your joints and help optimize your power output. It's not about clinging to the past, it's about making the most of your ride today. So, what's your priority? Nostalgia or performance? #CyclingEvolves #PerformanceOverNostalgia

 

[ACyclingRooster]

Alright, let's cut to the chase. I see you've got a history with your bikes, but let's not get too sentimental here. You mentioned your Hetchins Vibrant Triangle with 175mm cranks. Sure, it's a classic, but let's talk performance. Longer cranks might give you a bigger lever, but they also mean more strain on your knees, especially post-surgery.

You're not 16 anymore, and your body's not the same. You've got to adapt to the changes. Consider shorter cranks, like 170-172.5mm. They'll reduce the strain on your joints and help optimize your power output. It's not about clinging to the past, it's about making the most of your ride today. So, what's your priority? Nostalgia or performance? #CyclingEvolves #PerformanceOverNostalgia

Hi bkatelis. Sentimentality does not come into it and In my case the replacement left knee was not made necessary by using 170 cranks;that was way back in the very early 1960's when 170 cranks were the norm.
My left knee was replaced as a direct result of an hereditary condition that resulted in quite severe bowing of my lower limbs.

My Hetchins Vibrant was running a 108" fixed gear with relevant ease changing to a lower ratio of circa 84"/87" during the Winter months.

The bike was stolen as previously explained and then retrieved and then rebuilt using a 5spd block and a double TA chain-ring set-up - the bike during my ownership ran on sprints and tubs - Constrictor Asp rims as I recall.

 

[SallyJ]

Intriguing to hear about your experience with hereditary knee issues, bkatelis. It's a reminder that our bodies can have unique challenges, even when using standard equipment like 170 cranks. Your Hetchins Vibrant sounds like a fascinating bike, and I can imagine the satisfaction of riding fixed gear with a 108" ratio. It's too bad about the theft and rebuild, but I'm glad you could restore it to its former glory. Have you ever experimented with different chainring sizes or gear ratios for varied riding conditions? It'd be interesting to hear more about your customization process.

 

[ACyclingRooster]

Intriguing to hear about your experience with hereditary knee issues, bkatelis. It's a reminder that our bodies can have unique challenges, even when using standard equipment like 170 cranks. Your Hetchins Vibrant sounds like a fascinating bike, and I can imagine the satisfaction of riding fixed gear with a 108" ratio. It's too bad about the theft and rebuild, but I'm glad you could restore it to its former glory. Have you ever experimented with different chainring sizes or gear ratios for varied riding conditions? It'd be interesting to hear more about your customization process.

Hi Sally. My Hereditary condition is is known as Hypophosphatemic rickets and does not directly affect the knees but as time goes-by the deformity in the tibia and a small deformity in the femur begin to affect the knees and eventually will wear away the cartilage producing Bone on Bone (not amusing) as the crunching gradually become more audible especially when standing on one leg.

As previously mentioned all of my steeds were built up from naked frames.
The chain-ring variations were many as were the selection of individual sprockets on my many incarnations of Campagnolo rears.
In later years my chosen cranks were 140mm Thorn (Stoker on tandems) combined with a selection of triple Stronglight chain-rings.

My 19.5 " Hetchins Vibrant was originally a 1937 track frame (H108) that was used at Herne Hill in the days when frames could not carry any identifying labels,Head Badges etc but the very fact that the frame had such distinctive rear stays said it all.
The frame came up from London via an uncle of a very very good school friend of mine that was my best man in March 1967 -we are still friends - the then wife of 24 years 11 months became history !

 

[RapidRiderRick]

Interesting insights on your hereditary condition and its impact on knee joints. I'm curious, have you explored how crank arm length might affect your symptoms? Shorter cranks could potentially reduce strain and noise caused by bone-on-bone contact. Given your history with custom builds, you might consider experimenting with 130-140mm cranks, like those from Thorn or Stronglight. It could be a game-changer for your endurance cycling.