Rack Mount Stability

[5-7HEAVEN]

I just bought a used MB that had sat idle/neglected for three years. It has a Mitsubishi TLE43 engine, Staton chain drive and NuVinci hub. The bike is a 2000 Trek 6700 SLR w/ ROCKSHOX fork and 18" aluminum frame.

Is it just me, or do rack-mounted drivetrains seem EXTREMELY light at the front? I have a center-mounted Tanaka engine w/shift kit. It seems MUCH better balanced than my new MB. I DID have a STATON friction drive setup on my cruiser. It was somewhat balanced at the front(but heavy!), because it had a SECOND friction drive on the front wheel. The extra front weight kept the cruiser's front solidly on the ground.

How do you members w/rack-mounted drivetrains handle your bike's light front end? This bike weighs about the same as my center-mounted MB, but weight bias is way off!

 

[darwin]

Total wt for a fd is 16lbs you dont even notice it. I've carried more weight in groceries in a basket then that. Thats with a honda 50, i'm sure the sooby i have weighs even less.

 

[Happy Valley]

Yep, what he said^
No issues whatsoever on that with either TLE43 or EHO35.

 

[Deleted Member 4613]

My new rs 35/cvt bike is so well balanced, it's like I'm riding a bicycle, no sensation at all that there is a motor on the bike.

 

[5-7HEAVEN]

Maybe it's the NuVinci's extra weight.The front end seems VERY light, especially climbing the stairs w/the bike.

I'm also building a Staton twin-engined 29" bike. That'll add more weight to the rear end. Unsure if I'll be using another NuVinci hub on this one.

Maybe I'll add weight to the front ends.

 

[jander6442]

Just throw some tools in a bag on the front to even out the weight... maybe a beverage holder.

 

[5-7HEAVEN]

Just throw some tools in a bag on the front to even out the weight... maybe a beverage holder.

I'll be adding a handlebar tool kit, for sure.

Right now, the front/rear weight bias is not 50/50, of course.

Using a scale, 50lbs of 62lbs is on the rear.

That's 81%/19% rear/front bias.

In comparison, my Diamondback bike w/center-mount engine, shift kit and 8-speed cassette has 37lbs of 69.2lbs on the rear.

That's 53%/47% rear/front bias.

Unbelievable!

A three-quart fuel tank and my 15lb backpack(with tools) up front will help.

My 13lb. Fuggetaboutit chain wrapped up front would make it 50-something%/40-something% front-rear bias.

This bike might need to add over 30lbs. up front. The backpack and fuel tank are necessary items I carry on the center-frame bike. They need to be on this Staton/NV bike too.

In my opinion, without changing the front/rear weight bias, this bike is a death trap.

 

[loquin]

What's the ratio when you're sitting on the bike, leaning forward in riding position?

There should be plenty of weight on the front wheel then...

 

[5-7HEAVEN]

Hi Lou,

My concern is that sometimes I'll lean back on my seat unintentionally, especially after cresting a hill, or a long cruise. The front end is extremely light. A motorcycle racer friend once told that one of the most important features on a motorcycle is how the front end behaves. I rode the bike when I first got it. It felt okay, but I never pulled back on the reins.

No wonder my friend Rick could easily pull his front wheel off the ground. He had a Honda 35, Staton drive and NuVinci hub. He then replaced the Honda with a CY460 engine. Rick is in the Middle East right now. I should try to contact him.

 

[Virginian]

I have a rear mount GEBE system with a Tanaka 32cc engine. I find not problems at all with balance. It feels and rides just like a regular pedal bike, except it's much faster.