getting both bikes the same

radiation man

i have 2 bikes 1 is harder on the knees then the other, if i put both bikes next to each other shouldnt the chainwheels be inline with each other and the seats inline and both the same height.

napoleond

Geometry differences mean that they can be different.
You need a tape measure and a spirit level.

Get the bike that is good-

Make sure that the floor is level, place the bike so the rear wheel is up against a wall so the bike is coming straight out.

Measure the distance from the wall to the middle of the crank spindle
Measure the distance from the wall to the front of the saddle
The difference between the two is the saddle setback.

Measure the distance from the centre of the crank to a point, say, 140mm in from the tip of your saddle.
This is your saddle height.

Use the same technique to transpose these measurements onto the other bike, using the saddle height and the saddle setback.

radiation man

ive just done the measurements and will put them on here on weds night

MichaelW

Bottom brackets can vary in height so to eliminate this variable, measure from the BB.
I like an {x,y} coordinate to measure saddle and bar position.
Mark with tape the x=0 on your top tube using a plumbline (heavy weight on a string)

My saddle index is the front of the nose and my bar index is the web of the hand location. Being Norfolk bred but not born, my web is distinct.

careful

Measure the distance from the wall to the middle of the crank spindle
Measure the distance from the wall to the front of the saddle
The difference between the two is the saddle setback.

Thanks napoleonD. I have always used a plumbline but your method seems a lot less fiddly and less room for error.

radiation man

my measurements for both bikes are trek 1.5 54cm frame
back of seat to wall 42cm
front of seat to front of bars 50 and a half cm
wall to middle of pedal spindle 74cm
wall to front of chainwheel 84 and a half cm
wall to middle of crank 74 and a half cm
wall to front of saddle 69 and a half cm

trek 1.0 pilot 56 frame
41 and a half cm
50 and a half cm
75 cm
86 cm
76cm
69 cm
the trek 1.5 is the best ride the trek pilot 1.0 makes both my knees ache at the top

napoleond

You have 2cm bigger saddle setback on the pilot. move the saddle 2cm forward on the pilot.
You haven't done the other most important measurement - middle of crank to top of saddle 14cm in from tip.

radiation man

the seats of both bikes are the same 172 and a half cms

wardieboy

NapoleonD wrote:

Geometry differences mean that they can be different.
You need a tape measure and a spirit level.

Get the bike that is good-

Make sure that the floor is level, place the bike so the rear wheel is up against a wall so the bike is coming straight out.

Measure the distance from the wall to the middle of the crank spindle
Measure the distance from the wall to the front of the saddle
The difference between the two is the saddle setback.

Measure the distance from the centre of the crank to a point, say, 140mm in from the tip of your saddle.
This is your saddle height.

Use the same technique to transpose these measurements onto the other bike, using the saddle height and the saddle setback.

Top tip Mr Nap, thanks! I've now been able to set up my turbo to match the road bike.