GMC Topkick Dual-Suspension Mountain Bike

Product Description

Amazon.com The GMC Topkick 21-Speed Mountain Bike features a full-suspension, strong aluminum frame that utilizes a floating beam suspension design that is mated to a Zoom suspension fork with elastomer/spring technology. The Topkick's drivetrain starts with Microshift push shifters. These shifters control Shimano's tried and true TZ-30GS derailleur. The drivetrain finishes up with a strong aluminum wheelset featuring V-shape rim profile and high-flange alloy hubs. Stopping is handled by Promax disk brakes on the front and rear. These brakes are vastly superior to rim brakes, especially under adverse road conditions. True to it's GMC roots, this bicycle is rugged, good looking, and built for the long haul. GMC Topkick Mountain Bike Specifications Frame: 26-inch full suspension aluminum MTB frame Fork: Zoom CH-386 suspension fork 65mm travel Shocks: Kind Shock adjustable 650 pounds Chain: KMC Z 51 Crankset: Alloy ISA 335P 28x38x48 L170mm Front Derailleur: Falcon MF 31 T Rear Derailleur: Shimano RD-TZ30GS SIS 7SPD Shifters: Microshift TS-50 ADII index L3/R7 Brake Levers: GP 30 AP aluminum Brakes: LCHI DSK-320 disk brake 160mm Rims: Alloy black 26-inch X1.5 Tires:26 inch MTB Tread Stem: A-head TDS63K-8 EXT:100mm 15D Handlebar: HL-MTB 153 W: 600mm R:30mm Sadle: Padded Foam Seat Post: Alloy micro adjust 27.2 X 300mm with quick-release Amazon.com Bicycle Buying Guide Finding the Right Bike To really enjoy cycling, it's important to find a bicycle that works for you. Here are some things to keep in mind when you're in the market for a new bike: The Right Ride In general, bikes are broken down into three major categories: Road and Racing Bikes--As a general rule, road and racing are built for speed and longer distances on paved surfaces. Thinner tires, lightweight 29-inch (700c) wheels and drop bars that allow for a more aerodynamic position are the norm. Most road bikes, regardless of price, offer many gears for tackling both hilly and flat terrain. Mountain Bikes--With their larger tires, hill-friendly gearing and upright position, mountain bikes are very popular for all types of riding, both on pavement and off. Mountain bikes that are designed specifically for rugged trail use typically feature a suspension fork. Some may have rear suspension, as well. A quick change of the tires on any mountain bike--even one that you use regularly on trails--adds to its versatility and makes it a worthy street machine. Comfort/Cruiser Bikes--For tooling around on bike paths, light trails, or for cruising a quiet beach-side lane, comfort/cruiser bikes are the ticket. With a super-relaxed riding position, padded seats, and limited or no gearing, these bikes are made for enjoying the scenery and having fun with the family. The Right Price A bike's price boils down to three essentials: frame materials, bike weight, and component quality and durability. Entry-level--You'll find a wide range of comfort and cruiser bikes in this category, as well as some lower-end mountain bikes and road bikes. Most will have steel frames and components that are designed to last for several years with frequent use. Mid-range--Bikes in this range may feature a lighter aluminum frame with mid-range components that keep performing after miles of use. If you're looking for a quality bike that is relatively lightweight and will stand up to abuse, this is the "sweet spot." Most serious commuter and touring bikes fall into this category, as do mid-range mountain bikes with a decent front suspension. High-end--Racers and serious enthusiasts who expect lightweight, high-performance components will want to stick to this category. For road bikes, exotic frame materials (carbon fiber, titanium) and ultra-lightweight components can add thousands to the price tag. Mountain bikes in this class often feature advanced front and rear suspension technology, as well as components designed to handle lots of rugged trail action. The Right Size Fit is crucial for comfort, control, and proper power and endurance on a bike. Here are some basic bike fit tips: Stand-over Height--To find out if a bike's overall height fits your body, measure your inseam. Next, determine how much clearance you'll need between your crotch and the top tube of the bike. For a mountain bike, you'll want three to five inches of clearance. A road bike should offer between one and two inches of clearance, while a commuter bike should have two to four inches. Compare the stand-over height for a given bike to your measurements (inseam + clearance) to determine the right bike height. Top Tube Length--You can measure your torso to get a good estimate of proper top tube length. First, make a fist and extend your arm. Measure from the center of your fist to the end of your collarbone (the part that intersects your shoulder). Next, measure your torso by placing a book against your crotch with the spine facing up. Measure from the spine to the bottom of your throat (the spot between your collarbones). Finally, add the two measurements (arm length + torso length), divide the number in half and subtract six inches. This is your approximate top tube length. Compare this number to a bike's posted top tube length. You can allow for about two inches longer or shorter, as most bikes can be adjusted via stem length/height and saddle fore/aft position to make fine adjustments to the fit. Bikes for Women--Proportionally, women tend to have a shorter torso and longer legs than men. Bike makers design women's bikes that offer a shorter top tube and many comfort/cruiser bikes built for women may also provide more stand-over clearance. The Right Accessories When you make a bike purchase, don't forget these crucial add-ons: Helmet (this is a must!) Seat pack Lock Hydration pack, or water bottles and bottle cages Spare tubes Portable bike pump Gloves

Product Detail

• 21-speed mountain bike features a full-suspension, strong aluminum frame


• Floating beam suspension design is mated to a Zoom suspension fork with elastomer/spring technology


• Microshift push shifters and Shimano TZ-30GS derailleur


• Strong aluminum wheelset featuring V-shape rim profile and high-flange alloy hubs


• Front and rear Promax disk brakes work great, even in adverse conditions

CUSTOMER REVIEW



This is a good bike - the best feature is the dual suspension. Light and easy dropping off curbs on the way to work - huge difference from my hardtail mountain bike.



Disc brakes are nice to have, on front and rear - work much better than rim brakes. To adjust them hold the brake lever in and tighten them down via a hex wrench on the opposite center of the disc brake until the pads are flush against the disc, then turn back until the brake lever has enough play in it.



The rims are v-shaped, and narrow - much more so than my other bikes. It was quite a job to add tuffy liners to to the tires. I think I will have a bike shop change the tire next time they need it. The hard part is getting the tire off and on those narrow rims. The people at REI said to squeeze on the sides of the tire as you put it on, so both ends go deep into the rim.



Be careful when you put the front tire on that you have the fork facing forward. (I had it backwards the first time). Make sure the big round points on U part of the fork point towards the front of the bike.



The tires are very knobby. If you ride on the street a lot you might want to change them to something with a smoother tread in the middle.



The bike weighs 38 pounds put together - not exactly light, but since I ride for pleasure and exercise, and don't plan to race, the weight is fine.



If you get it for less than 150, (what Amazon is selling it for the week of Feb 20), it is quite a bargain. (disc brakes by themselves often add $100 to a bike).



I raised the seat pretty high for a comfortable ride at my height, and found the handlebars are two low. I fixed this by adding some handlebar extenders which allow me to be more upright when I am not braking.



To my knowledge you can't raise the stem on the handlebars without adding a spacer. If anyone finds out otherwise, please comment to this post.



Another possibility (besides handlebar extensions), would be to replace the handlebar with one that has more of a rise to it.



The Topkick is made by Kent Bicycle Company for GMC. They also make some Cadillac Mountain Bikes - the Cadillac AM2.4 and AM2.7, which are sold on Amazon. They are both dual suspension with disc brakes and have a very similar frame as the Topkick. Both bikes sale for over $1000.