Knee angle on ICE Adventure RS recumbent trike

[PAB855]

At what angle should my knee be on an Adventure RS recumbent trike which is normally used by my wife. She is 5ft 6in and I am 6ft and 0.5 inches ! Perhaps a suggestion of how far forward I need to adjust the boom would be a simpler solution as it was set up for her by a knowledgeable person after purchase when new.

I m not concerned too much about how well the gearing will work for now as this exercise is more of an experiment than anything else and it does have a retrofitted e assist pedal sensor with a throttle .

Cheers

[[XAP]Bob]

I start off with “heel on the pedal” when straight, and adjust from there for comfort.
The exact distance will vary slightly as you move up and down the seat.

[PAB855]

That sounds simple, much the same as a bicycle!

Thanks Bob

[a.twiddler]

If there's 6" in height between you and your wife, unless you have a very wide range chain tensioner, you will need to add chain links to accommodate the extra boom length, which makes it awkward for two people of different heights to quickly adjust the length for their use. I know some bikes/trikes do come with such a thing, or can have one as an extra fitting. Perhaps the ICE Adventure RS already has one.

Being 5'5" myself, I've had to cut the boom on my last bike, a HPV Grasshopper, to get it to fit (as per manual). If that's the case with your wife, you need to make sure there's enough boom left inside the frame when extending it for a taller person.

Just some things to consider.

[Skids]

Hi, While Bob is correct I would make sure that you are not over extending your leg. I'm guessing that you have a mesh seat which has some give in it plus its possible to slouch in the seat moving forwards towards the pedals. I find it best to start with an initial position and then ride adjust ride until you narrow down to the best boom length.

If you plan to share the trike ICE sell a device that allows the boom to be moved without having to change the length of the chain:

the Easy Adjust kit 03391

[PAB855]

Many thanks for all your helpful comments.

I'm soon to do a road test and have also set wheels in motion for one for myself .

Fingers crossed

[pjclinch]

On chain lengthening/shortening, if it's something that would be needed often then Hase have a "swithcback" in the chain on a Kettwiesel to compensate for lengthening or shortening the boom: it might be possible to fit one to an ICE?

(Edit, I see this has already been covered by Skids)

For basic length setup I also use the standard "heel on the pedal at full stretch" as the starting rule of thumb. Fettle a bit in and out of that and see how it feels, but it does seem to be a good start. I seem quite sensitive (by way of hurting knees after any distance) if I have it too short, again same on the 'bent as the upwrongs.

Pete.

[Marc]

At what angle should my knee be on an Adventure RS recumbent trike which is normally used by my wife. She is 5ft 6in and I am 6ft and 0.5 inches !

Lets start at the front: What is the crank length on the Adventure?

The "usual" crank length options (165mm, 170mm, 175mm) are already fairly long, I'd even say too long, for her. On a recumbent, a fitting crank length (eg. much shorter) is even more important. Thats what my knees tell me, anyway...

For instance:
At 1.75m, I need 155mm cranks or shorter with recumbents. Riding my trikes with 170mm cranks will lead to knee pain after about 30km. 165mm cranks will lead to knee pain after about 50km. With 155mm cranks I can ride all day long without any knee pain, though.

Fun fact:
I've tried 145mm cranks on my VTX for 3,000km, but it felt rather odd and I never liked it. The other trike has 155mm and it just felt right. The 143mm cranks in my Milan velomobile on the other hand, feel just as good as the 155mm cranks in the trikes. I assume its due to the lower seat angle and higher bottom bracket of the Milan, compared to the VTX.

If you never thought about ideal crank length, read this (further down are crank length calculators):
https://www.applemanbicycles.com/resour ... ank-length

That crank length article has uprights in mind, with recumbents even shorter cranks can be beneficial:
http://www.recumbents.com/wisil/misc/crank_angle.asp