Crank and Chainrings Upgrade Advice
 

My current setup is all Shimano 46/30 175 front crank 11-36 9 speed cassette . I'd like more top end . Just not sure how much to go with . The 30 chainring is fine It's the 46 that just isn't quite enough .

Also the current crank price checks at $45.00 . Is there any great advantage to putting on a more expensive crank? Would a $150 Crankset be way overkill ???

What about crank arm length . My current is 175 . I see those but also see shorter ones . I'm 6' tall . Around 33.5 inseam

The 16-tooth jump in chainrings is close the the max for good shifting, and may be all your rear derailleur can take up. If you go bigger with the large, would you be okay losing the lower gears? And you'll need a new chain, of course.

You should be able to find the max chain wrap specs for your RD--look up the part number on the inside of the body.

175 cranks is probably right for your height.

It's hard for me to imagine the value in a $100 upgrade but I'm just a recreational rider.

a $150 crankset might have nicer chain rings and maybe better finishing, but you’ll likely not notice any difference in performance. If 175mm works for you, why change? A compact crankset (34/50) will give you more top end and still give you a 34:36 low gear, which is pretty damn’ low. Unless you have some serious climbing challenges, this should be plenty low enough. Going with a 34/50 crank won’t tax the chain wrap capacity of your current RD (assuming your current setup works) but you’ll likely need a longer chain. How old (how many miles) is your current chain and cassette? If they’re very old/worn, a new chain may necessitate a new cassette.

With a 46/11 high gear ratio, at 90rpm pedal cadence with a 27" tire diameter, you are going 30mph, not fast enough???

^This^ How fast do you want to go? Or...just how slow is your cadence?

I don't know my average cadence . My average speed on a Hybrid 700 x 45 bike on a 20 mile ride is 12 MPH On a 10 mile road no stops it's 13.5 . But that depends on the road . However at 66 I rather doubt I'm pushing a 90 cadence . .especially on graveled Blacktop hilly country roads . Much harder ride then smooth bike trails are .

My bike has Deorge RD and Acera shifters . I just noticed that my riding partner has the same bike with 3 chainrings . Pretty sure the first 2 are 48-38 . He put a 9 speed cassette and upgraded his RD and Shifters . As it was an 8 speed to begin with . When we swap bikes I average roughly 1.4 miles faster with his bike . SO I figured getting larger rings would get me more speed . It's a hybrid . I rather doubt any average rider regardless of age could maintain 90 cadence . I just notice my bike feels like it has a dead spot where I'm in between . Just trying to eliminate that .
I only mentioned a NEW CRANK because I don't see where Shimano offers chainrings without the whole crank . AM I wrong ? Thanks

Speaking as a fellow geezer who is now gently entering the twilight phase of my storied cycling career, I would guess that, at least, a partial solution for your "need for speed" TM :) is not bigger gears but lighter (and more supple) tires and tubes. One example is the Rene Herse Snoqualmie Pass tires, there are other brands that I have heard good things about (in terms of performance). Perhaps moving down to 38c or 32c widths as well. I can almost guarantee that you are not spinning out, on level ground, your (46x11) 114 gear inch setup. Having lightish wheels will be a (big) positive step towards accomplishing your goal of higher performance.
There is a whole rabbit hole of things to do to be faster but light and supple tires are a fast and easy, but not necessarily cheap way to go.

I'll check that out thanks . I suppose I could get a road bike .:) Thanks again for the input

Yes, a road bike is part of the rabbit hole I was speaking of, with an almost infinite number of options available. I don't know what your inclinations are about acquiring another bicycle and/or your mechanical skills/abilities but to go fast and have a good time you don't need the latest and greatest. There are hundreds of thousands of bikes that were once state of the art and a total kick to ride then and are a total kick to ride now, but are now 'obsolete' and almost discarded like an old shoe and so can be had for a decent price.
One caveat I would make is to make sure that there is clearance for at least for a 28c or better yet a 32c tire. If you are not familiar with the supple/larger tire revolution please read up on it. This is a case where you can have your cake and eat it too. A supple, lightweight tire in the above mentioned sizes with the appropriate tire pressure will increase your comfort as well as your speed.

Rick53

46/11 high gear with 700 X 45 tires is 20% higher than professional cyclists used until fairly recently. Is this the only gear you use? If you are averaging 12 mph it seems you would rarely use that gear for general riding.

The dead spot(s) you allude to are the drawback of wide range double drivetrains currently in vogue, particularly those with less than 12 rear cogs. Your average speed will most likely go UP if you get LOWER gearing with more evenly spaced gears in a range that is more useable for you. Your partner's triple drivetrain most likely has more useable gears in your 66 year old power range that you find comfortable. Shorter cranks can also help with this for someone with your inseam meaurement.



How do you know you are 1.4 mph faster on your friend's bike? And is your friend SLOWER on your bike? Same computer calibrated the same? Same tires? Are the saddle and handlebars identical and in the same relationships. A difference of a few millimeters in your riding position can make a surprising difference in power output.

90rpm is an average pedal rpm for riders who train for speed or who are in a race. I am 60 years old and train at that pedal rpm often, but I am going between 19 and 20mph. If your average speeds are only 12-13 mph then you do not have any gearing problem at all, if anything you are pedaling too slowly in too high a gear. By simply changing gears down so you are pedaling at a little higher rpm you will get a faster top speed once you are used to it. It is the same as a gasoline engine, up to a limit they make more and more horsepower at higher rpm because there are more power-pulses per minute, so even if the engine is not as efficient at a higher speed, the higher number of smaller power pulses per minute give it an overall higher power level at the higher rpm.

13mph is very low speed and low-performance cycling, and the number-one factor in going faster at that speed is the rider, not the equipment. Until you get up to average speeds around 20mph the equipment does not make any difference at all. If you get to the point where you can average 16 to 18mph while sitting up pedaling, then getting a "road bike" with drop bars and the horizontal riding position it allows will get you close to 20mph. Today I was riding my mountain-bike with another rider on a paved flat route and I had no trouble going 20mph for a number of miles on it because I had the bars set very low so I could get down in a road-bike position, and I also put 80psi in the tires, which helps. You may gain a mph just by running high pressure in your tires.

You have a long, long way to go before it is the equipment that is holding you back for sure.

How much would better wheels play in things . I have a Specialized Vado 4 that I picked up at an insurance auction very cheap because someone had stolen the battery , seat /tube . I ordered a battery 4 months ago. That bike weighs 12lbs more without the battery . I believe it's 48 with 10 speed cassette . I've ridden it on 20 mile rides . It is heavy so uphills it's harder . But on flats that thing rolls like it's on glass . I have to assume being a 4,000 Bike the wheels play a large part in that . It also has solid thru axles vs QD Skewers so I suppose that makes a difference as well .

Just for clarity: is that Specialized Vado 4 the bike you've been referring to in all your posts in this thread? If so, I imagine that several of the people who have contributed here would want to revise their recommendations.

No it's not . And to clarify so there's no mistake : I have no battery for it at the present time . When I get one I plan to sell the bike for profit . I bid $100 and got it for that and delivery taxes of 47.00 . It's costing me $1000 for a battery . And it's basically a brand New machine . I've hooked up juice to check the computer which shows just 214 miles . I was just in the right place at the right time . . I've sold another E-Bike already -So don't see me keeping this either . You have to really like long rides to get any exercise: I don't ;)