chicbicyclist

I asked two of the LBS that I've had very pleasurable relationships with in my immediate area about this but they gave me two different answers.

I want to replace my tires, currently 26X1.95 mtb, to slicker, thinner ones for more efficiency. My bike is about 85 lbs(35 lbs actual bicycle, 30 lbs batteries-goes on my rear rack, 20 lbs or so for the front hub motor). I am about less than 120 lbs so you can say that I'am comparable to a 180 lbs rider because of the extra weight.

One bike shop said that I should stay with 1.75 or higher, and another said I should be fine, that the weight shouldnt be an issue with generic mtb tires(1.25 all the way to 2.00++) so long as I don't use the thinner road tires.

So which is it? Can I use thinner tires, or should I stick with wider ones?

Thanks.

stapfam

Had a friend that weighed around 180lbs on an MTB and for years ghe used 1.95's. then he changed to 1.8's and he got more control over the bike offroad. Presume you are talking road use though and he used to fit 1.5 slicks with no problems.

roadfix

A good quality set of 1.25 tires can handle much more than your total weight. Consider a fully loaded touring bike or even a tandem using 26x1.25 tires....they seem to handle these loads just fine...

chicbicyclist

Oh yes, this will be a city/urban utility kind of bike. Zero offroading at all, not even interested in that sort of thing.

Thanks for the answer guys, any recommendations for good quality slicks(and I mean slicks, no fancy treads thats only there for cosmetic reasons to make it look "sporty")? There's such a vast assortment and variety out there, its quite daunting to choose which ones! Hopefully, something that will not puncture easilly. Doesnt have to be top of the line, but economical and practical for the price points.

I am eyeing the Tom Ritchey slicks 1.4 right now.

Retro Grouch 

I'm running Continental Town & Country's on my beater. I don't know the exact width without looking but they must be about 1.8 or 2.0 inches wide. It's about a 75psi tire. I bought them because I was able to get them cheap and because I was advised by somebody that they were standard spec on many police bikes due to their puncture resistance. I'd think that would be a good choice for your usage.

Big Tommy C

I ran 1.95s on a 30lb bike while I weighed 260 and was carrying 100oz of water in my camelback...I think you'll be fine. ;-)

PS dieting works

closetbiker

That's a pretty hefty rig. With a motor assisiting in driving it, I wonder why you're wanting to have thinner tires. It's not like it's a performance machine, and the extra width in bigger tires aides not only in speading out the shock of the ground transferring to the bike (and to you), there is the possible additional elevated risk of flatting with thinner tires.

chicbicyclist

Well, it will improve my battery range by 25-30%(per manufacturer recommendations), without having to buy expensive or heavier battery kits. Right now, I'm doing 25 miles per battery charge on flat ground, and would like to get to at least 30 miles, and do a 20 miles round trip to the beach(where I hang out half the time)without using the car.

Many cyclist will probably frown on the electric assist kit, but hey, its better than a car, and its still a bike

Portis

Ritchey Tom Slick's are rated very good. I bought the 1.4 size as it gives just a bit more stability than a 1.25 will provide. A 1.4 gives a noticeable improvement and still the ride is pretty good. Skinny tires greatly improve the harshness of a ride, you will feel bumps and such more. It is a trade off. That is why i went with a slightly wider slick, they are very nice.https://www.mtbr.com/reviews/Tire/product_84992.shtml

Machka 

I'm not frowning on the electric assist kit, but I'm curious why you would need a motor. If your main ride is a short 20 mile trip to the beach and back, you can easily cover that in approx. 40 minutes each way by pedal power ... and get a bit of a workout in the process.

And if you were to remove the motor, you could easily go to narrower, smoother tires.

chicbicyclist

I don't need a work out, in fact, I need to gain weight(I'm one of those people who are blessed/cursed with a fast metabolism). I'm not a "hardcore" weekend recreational warrior either, it is my main form of transportation in the urban core of the city. It's cheaper and sometimes faster, and well, its cool. I don't care if I don't have the newest and lightest gear, if a bicycle moves(and looks cool), it's fine.

I'm not an enviro-freak either, so I don't care about the environment that much that I try to live a really simple life as much as possible, although I do consider myself a bleeding heart liberal.

I don't care if I own a car or not(I own a gas guzzling 64 mustang, so that kinda evens it out), they have thier uses, and I use public transportation if I need to so I'm not a car-free activist, though it does make me smile that I'm saving some money on gas.

So to answer your question, I am a Utility Cyclist . In quite a hilly city. I use the motor to make cyling easier for me(main complaint of the general public when it comes to cycling for commuting/utilitarian use: it's too hard, and the hills!) and demonstrate that it is indeed a viable form of transportation for short to medium distances, especially in the urban core of San Diego.

20 miles of unpowered cycling is out of the question for me, and I hardly consider it "short". Hehe.

closetbiker

You're right there!

Machka 

I agree that it is a good alternative to other forms of motorized transportation. My father has been toying with the idea of doing something like that with his Cattrike.



Cycling isn't about weight loss. In fact, cycling can help you develop muscle ... which weighs more. Cycling is about fitness. And if you currently think 20 miles is a long ride, that tells me that your fitness level needs a little work.

I would really be impressed with your setup if it were possible to ride without the motor, and then just turn the motor on now and then for a bit of a break. That's what my father has in mind.

chicbicyclist

That's actually what I do most of the time(or try to). On flat ground, the bike isnt any different from an unequipped bike, well, it is harder to start from a stop, but thats where low gears comes in. Once you got your speed rolling, you probably will not notice anything weight-wise(like somebody mentioned above, its like carrying stuff as if you're touring, only you have the option of a motor to aid you). On hills, you deffinitely need to turn the motor on. Oh yeah, I forgot to mention that you have to actually pedal before the motor starts, but some systems have power-on-demand controls.

The trike would be even better, since you wouldnt have to worry about bike-weight imbalance(there's always lighter higher-end batteries which weighs about half as much). One main problem I have to admit though, is that once you got used to that speed of riding, you probably will not want to go back to bicycling unassisted.

But yes, it is after all, an electric-assist kit. You need to pedal along to get the most out of it.

ken cummings

What kind of 30 lb battery do you have? Lead/acid? There are better batteries (for more money ). Some batteries can charge up in the time it takes you to stop and have lunch. There are motor assisted bicycles with motors that weigh way under 20 lb. I quess I am saying we need to know a lot more about your machinery.

chicbicyclist

Yes, it is indeed a 30 lbs Lead acids. They are stock batteries and don't expect them to last more than two years with my current usage, and will be deffinitely looking at NiMh, and a promising new tehcnology called NiZn that will be cheaper than NiCd and less weight than SLA. But right now, for the cost and reliability, the SLA is working out really well for me.

My motor is actually around 15 lbs, so I'm a bit overestimating with my weight figures above.

More specs about my system:

manufacturer is Wilderness Energy

400 watt Brushless front hub motor mounted on a rim(can you actually convert this to become a rear mounted hub motor? I mean like change the axel, put some gears, etc?), about 15 lbs, deffinitelyl less than 20.

Thumb throttle for variable speed controls, and power indicator

36 v (three 12 v, 12 am/hour) sla batteries, about 30 lbs

a controller, with a key switch

a 36v charger

some wires to connect everything

And thats pretty much it.

The system has a "real world range" of about 25 miles with a top speed of capable of reaching 20mph without peddaling on flat ground. Charging takes 4-6 hours, better if you got better batteries and chargers.

Eatadonut

so are you not pedalling at all? Even if you wanted to do the electric assist, I bet you could easily double your range and go even faster if you pedalled along.

Also, thinner tires will help, and yeah, they'll support your weight no problem: think of those of us who weigh 210 on 21mm tires, or do jumps on 1.75" tires.

chicbicyclist

I do pedal, I already factored that into my range figure. Not pedalling will probably give me less than 20 miles. The no-pedalling figure was for the top speed.

ken cummings

I checked a site for ZAP a local company for electric vehicles. The design speed for their street bike conversion kits is 15 MPH. have you tried accelerating slowly and keeping your top speed down to extend the range? Might give you the distance you need until the battery upgrade. Given a lower speed you might get away with a smaller and lighter motor.