Changing gearing on my Vado 5

[Sierratim]

@TS25, @Sierratim: I gave my Vado a test ride (shopping, and carrying 23.1 kg = 50.8 lb of cargo). Vado works flawlessly and silently now. Yes, I temporarily secured the bolts with zip-ties before the ride and will remove them only after any long ride (e.g., on Sunday).

A new home bike mechanic is born!

 

[Stefan Mikes]

Too bad. Good to know 9.8 Nm was too much.

So you used less Nm on the Specialized bolts afterwards?

For anyone interested: I have made shopping for aluminium chainring bolt-sets of the the kind we have been discussing. One of manufacturers has explicitly specified the tightening torque: 3 Nm. No wonder I pulled the thread...
(But other producer gave 7-8 Nm: steel bolts?)

 

[TS25]

For anyone interested: I have made shopping for aluminium chainring bolt-sets of the the kind we have been discussing. One of manufacturers has explicitly specified the tightening torque: 3 Nm. No wonder I pulled the thread...

Now that you know the correct torque for those bolts you could mount your red chainring and get out for some comparison runs to proof that it is in fact the fasterestest.
Better than just looking at it hung up on the wall thinking: oh boy, how fast could I be if I only had ....

 

[Marcela]

For anyone interested: I have made shopping for aluminium chainring bolt-sets of the the kind we have been discussing. One of manufacturers has explicitly specified the tightening torque: 3 Nm. No wonder I pulled the thread...
(But other producer gave 7-8 Nm: steel bolts?)

About 48 in lb (3nm) sounds about right for that size fastener in aluminum.

 

[Sierratim]

About 48 in lb (3nm) sounds about right for that size fastener in aluminum.

Might be high; https://www.convertunits.com/from/newton+meter/to/inch+pound

 

[Marcela]

Might be high; https://www.convertunits.com/from/newton+meter/to/inch+pound

Correct. Knew it was 2.2 ft lbs, my multiplier failed me. Though 26 in lbs does sound light. If it’s a tapered bolt head the 26 would sound better.

 

[Sierratim]

Update on the gearing, and new chain; so far, so good after several longer rides! Shifting is smooth and reliable, though the transitions between the last 3 largest cogs is a bit rougher as there are bigger tooth count jumps to get up to the 50t cog. No visible chain damage.

I rode out to the steepest grade I know of (that isn't a crazy MTB trail) to test the new granny gear.

View attachment 71664View attachment 71665
The County Public Works Dept has this road section signed with a grade of 31% at the top and bottom as a warning to trucks. I can't confirm the grade on our USGS topo maps, but they have a minimum contour interval of 40 feet so they leave a lot to the imagination. My take off these maps is that the max grade is more like 22%, but all I really cared about is a test for the new granny gear. It worked great, shifted into the largest cog smoothly. Didn't need to stand to get to the top, unlike last Spring when I rode this with my 11-42t cassette. This gearing change will do the job for me, i.e. guaranteeing I can get home regardless of how tired I am!

Got home with 27% battery remaining after 26+ miles and 2,600 of climbing on a beautiful fall day.

It was a wet afternoon so I talked my wife into driving out with me to this steep road grade to check the 31% grade posted by the County. As I slowly rolled down the grade she was watching the slope on her inclinometer (retired Engineering Geologist). It hit 17° (31%) on a section near the top that was maybe 50 yards long. So, the County signage is confirmed, this is a 31% grade!

I had to help with grocery shopping for this favor but they had Deschutes Black Butte Porter on sale so it all worked out!

 

[Rixtory]

I also like Sheldon Brown's Gear Calculator. Gear inches for various combos of wheels and gears and mph for various rider cadences. Handy for estimating how a gearing change might impact your top speed for you normal cadence range...

Coming in late to the party - Ditto on Sheldon Brown... I always went right to his site or his Harris' Cyclery site for anything to do with my bikes. He was a godsend in 2000 when I was contemplating switching out my old 6speed double & Biopace on my '86 Cilo when trying to make some major upgrades.

 

[Mike Moore]

P.S. Needless to say, I paid attention to replace the chain in the proper Narrow-Wide pattern

Stefan, can you elaborate as to what the proper Narrow-Wide pattern is with regard to the installation of the chain?

 

[Stefan Mikes]

Stefan, can you elaborate as to what the proper Narrow-Wide pattern is with regard to the installation of the chain?

Regardless it is a Narrow-Wide or Wave chainring, you should always look at the chainring and the chain from the top, You will notice some chainring teeth are wider than other (they might be shorter at the same time, but always wider or located to the outer side). The point is to put the chain with the wider link onto the wider tooth. That's it. If placed properly, you will see how the chainring teeth perfectly fit the chain.

Sometimes, there is a diagram on the inside of the ring how the chain should be placed.

 

[kahn]

Stefan, can you elaborate as to what the proper Narrow-Wide pattern is with regard to the installation of the chain?