Shorter Crank Arms

[rocky.28965]

Anyone fitted shorter crank arms to a Yamaha PW on a Fullnine RC.
I can easily get pedal strike on mine.

 

[BJep]

Hi- I am wondering the same thing. I am thinking shorter cranks on my Haibike Fullseven,7, Sduro. Yamaha PW as well. I have never had as many pedal strikes on my previous EMTB's, as I do now. I am pretty confused as the BB seems exactly same height off the ground as the 2 other EMTBs we have

 

[Hai Volume]

Hi- I am wondering the same thing. I am thinking shorter cranks on my Haibike Fullseven,7, Sduro. Yamaha PW as well. I have never had as many pedal strikes on my previous EMTB's, as I do now. I am pretty confused as the BB seems exactly same height off the ground as the 2 other EMTBs we have

Too much sag in your suspension? Are your other e-bikes hardtails, because rear suspension requires a higher unladen BB height to end up with a similar BB height with rider aboard.

 

[Hai Volume]

I'm also curious about crankarm compatibility. I *think* the bike uses standard crankarms, but not sure. I wouldn't mind 170's instead of the stock 175's to quell the occasional pedal strike that I get. For my XDURO Allmtn 6.0, it's not a big issue, but I do notice more strikes on this bike compared to my analog mtn bikes. Part of that is I'm just spinning at a higher cadence more often to stay in the motor's "power band." Then again, maybe I just need a few extra psi in the rear shock.

 

[drjarvis2003]

You can get shorter isis cranks from Miranda, I would go for 165mm though.
Merlin cycles sell them. 35 quid.

 

[BJep]

Too much sag in your suspension? Are your other e-bikes hardtails, because rear suspension requires a higher unladen BB height to end up with a similar BB height with rider aboard.

One is a hard tail but the other is a Cube full sus. You might be right about sag- I'll check again- but I also thought it might be the pedals- just that bit bigger. I wondered if anyone else had it with Haibike in particular

 

[rocky.28965]

I have the suspension set fairly firm & I'm only 140 lbs.
My previous non assisted ride was set the same.
Never had the same issue & it was only 24'' where as the Haibike is 29''.
I think it's the extra width, the pedals are further apart.
They could be a bit closer in as they clear the rear forks by more than a inch.
165's would certainly help.
Would anyone know a make or part number.
Not that easy getting parts in NZ.

 

[SteveS]

I have an sduro fullnine 6.5 and I seem to have more pedal strikes than I expected, but I'm also about 30 lbs heavier than I expected... I experience strikes mostly when the rear suspension is compressed. Can you engage lockout and see if that makes a difference?

 

[rocky.28965]

Rather than buying longer cranks, any thoughts on fitting a longer shock?

 

[Wiltshire Warrior]

shorter cranks wont make any difference - not where I ride anyway - some of the ruts/rocks I end up in are up to my wheel hubs

 

[Wiltshire Warrior]

I have an sduro fullnine 6.5 and I seem to have more pedal strikes than I expected, but I'm also about 30 lbs heavier than I expected... I experience strikes mostly when the rear suspension is compressed. Can you engage lockout and see if that makes a difference?

You might be blowing through the last 50% of the shock stroke ( i was) so I fitted the large volume spacer - and that has made a huge difference - only trouble is, I need to fix 2 of my other bikes now!

 

[rocky.28965]

You might be blowing through the last 50% of the shock stroke ( i was) so I fitted the large volume spacer - and that has made a huge difference - only trouble is, I need to fix 2 of my other bikes now!

Sounds interesting.
What does that involve?

 

[Gofurtherfaster]

shorter cranks wont make any difference - not where I ride anyway - some of the ruts/rocks I end up in are up to my wheel hubs

up to my hubs in ruts!

 

[Gofurtherfaster]

I like minus length cranks, -165 is my fave.

 

[Wiltshire Warrior]

Sounds interesting.
What does that involve?

Dead easy - first get the spacer I went from the stock small one to the large one

1 deflate the shock
2 unscrew the air can
3 Slide down the bottom out plate
4 unclip the standard spacer
5 clip in your bigger spacer - add some slick honey at this stage if you want
6 screw the air can back on
7 reinflate
8 go out and ride and to find the rear end transformed

I think anyone > 90KG on the scales needs to do this.

Takes about 5 mins and no tools required.

 

[Gary]

I think anyone > 90KG on the scales needs to do this.

Some suspension designs might, others won't. it depends on the bike's leverage curve and rider preference more than rider weight alone.

 

[rocky.28965]

I'm only 65kg so I guess it won't help me much.

 

[Wiltshire Warrior]

I'm only 65kg so I guess it won't help me much.

all depends if you are bottoming out on long rough decents with the occasional air time, its a very unsetteling felling which cant be helped by air pressure. if you dont know what I am describing then perhaps you are lucky dont have the problem!

I have it on my Yeti and Heckler and Moetrra -

 

[33red]

My 2017 hard 7 came with 175, after 2 months i switched to 165, much better

 

[33red]

You can get shorter isis cranks from Miranda, I would go for 165mm though.
Merlin cycles sell them. 35 quid.

I looked at Miranda and they have 6 sides, my 2017 Yaamaha has 4 sides(square), do you have any idea where 155 or 160 are available? Thanks
Ps. I started with 175, now i have 165.

 

[rsilvers]

Long cranks make no sense. I actually saw an article that said short cranks are not as efficient because you have less leverage. That is not how it works. You can just use a smaller chainring and get the same end result. The reason for long vs short cranks is not to get more leverage - it is to match the leg's kinematics.

 

[Jirkovo]

Haibike Manovella, Sduro Quadrato Yamaha Bici Elettrica, 152mm | eBay