The $1,800 Used Bike and the Sticky Throttle
A private seller is asking $1,800 for a 2008 250cc standard motorcycle with 19,400 miles. You have cash and a 20-mile ride home on a two-lane road before dark. In the driveway, you do a quick pre-ride check. The throttle grip does not snap back when you release it; it stays about one-third open. The front brake lever pulls almost to the grip before the bike slows. The chain has about 50 mm of slack at the midpoint, and the owner says the spec is 25–35 mm. Both tires are at 20 psi front and 24 psi rear; the sidewall says 28 psi front and 32 psi rear. The oil sight glass shows no oil at rest, but the owner says it 'shows when running.' The engine starts easily. The seller says the throttle cable 'just needs lube' and that you can fix the brake after you get home. You have basic tools but no trailer.
1. Which findings are stop-ride defects, and what makes each one dangerous?
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The stop-ride defects are the throttle return, the front brake, and the chain. A throttle that stays one-third open means the engine can keep driving the bike after you close the grip; at a stop or in a panic, that is a loss-of-control risk, not a maintenance inconvenience. A front brake lever that pulls to the grip suggests air, a leak, or a failing master cylinder; the brake may fade or fail when you need it most. A chain at 50 mm against a 25–35 mm spec can jump the sprocket or lock the rear wheel. The low tire pressures and the dry sight glass are also serious: low pressure changes steering and traction, and no oil at rest may mean the engine is running dry. Because the bike is not yours yet, you have no reason to accept any of these risks on a 20-mile ride.
2. What would you check before even a low-speed test ride?
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Before a test ride, I would confirm the throttle snaps closed from full lock in both directions with the engine off, then with the engine running. I would pump the front brake and check for a firm lever, no sponginess, no leaks at the caliper or master cylinder, and a working rear brake. I would check chain slack at the tightest point, adjust or reject it, and inspect sprocket teeth. I would set tire pressures cold to the sidewall or manual spec and look for cracks or nails. I would check oil level the correct way: bike upright, engine off, on level ground, after the specified wait. I would also look for fork leaks, loose spokes, bad steering-head bearings, and working lights. A test ride is only reasonable after the stop-ride items are corrected; otherwise I am testing a bike that can hurt me in the driveway.
3. The seller offers $200 off if you ride it away now. What do you decide, and why?
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I would decline the discount and not ride it away. The $200 does not change the risk: a sticky throttle, a weak front brake, and a loose chain can combine badly at the first stop sign or in traffic. I would either arrange a trailer, pay for a shop inspection and repair before riding, or walk away. If the seller will let me adjust the chain and tire pressures on site, that still does not fix the throttle or brake, so those must be repaired first. A good deal on a motorcycle that cannot be controlled is not a good deal. The decision rule is simple: if I would not let a friend ride it home, I should not ride it home either.