Just got myself a 2008 Honda CBR600 last month, decent price, looked okay at first glance. Figured I’d document the usual headaches these older bikes throw at you, ’cause yeah, they all got ’em. Learned the hard way myself this past weekend. Here’s how it went down:
The Electrical Goblin
Took it out for a spin, noticed the headlight dimming when I hit the horn. Weird, right? Pulled over, popped the seat off. Started poking around the regulator-rectifier. That thing? Mounted right above the rear cylinder bank, cooking itself silly. Felt the wiring connector – hotter than my coffee. Found melted plastic inside the plug, wires looking crispy brown. Not good. Solution was simple but messy: unplugged the cooked mess, cleaned the pins best I could, but honestly? Needed a whole new R/R unit. Swapped in a known good one (checked the connections weren’t burnt this time!), made sure the mounting spot had airflow. Heat kills these parts.
Carbs Hate Sitting Still
Bike had been sitting a while before I got it. Started fine cold, but once warm? Would barely idle, bogged down when I gave it gas. Felt like it was choking. Knew the drill – carbs gummed up. Had to pull those suckers off. Four carbs stacked together. Took my time, disconnected fuel lines, throttle cables, the whole shebang. Popped the float bowls off – nasty, varnishy fuel gunk clinging everywhere. Used carb cleaner like it was going out of style, poked through every little jet with a thin wire (gently!), blew compressed air through every passage. Biggest pain? Getting the carb bank bolted back on the intake boots without pinching anything. Took a lot of wiggling and foul language. Fresh fuel after reassembly? Night and day difference.
The Dreaded Clutch Stickyness
After sorting the carbs, went for another test ride. Clutch lever felt… off. Grabby. Hard to shift smoothly, especially down into first when stopped. Sounded like gears grinding sometimes. Paid the price for forgetting to check the simple stuff first. Drained the old oil – looked kinda burnt, smelled funny. Pulled the clutch cover off (messy job, oil everywhere). Inspected the clutch basket – sure enough, grooves worn in where the plates sit. Notched up real bad. Those grooves make the plates stick instead of sliding smooth. Sanding them down helped a bit temporarily, but a new basket is the real fix down the line. For now, swapped the friction plates and springs with new ones since they were tired anyway. Refilled with proper motorcycle oil? Shifted like a hot knife through butter.
Weeping Fork Seals
Noticed some oily streaks on the lower fork legs after a week. Classic fork seal leak. Front end felt a tad mushy too. Don’t need fancy tools, just patience. Cleaned the seal area super well with brake cleaner first – sometimes dirt gets stuck under the lip causing leaks. Used the “buddy system” trick: gently pried the dust seal down, slid a thin piece of plastic (cut from a milk jug!) up between the fork tube and seal to clear any grit. Pumped the forks a bunch. Worked! For now… saved myself a full seal replacement headache.
Random Sensor Freakouts
After all that, thought I was golden. Then last Tuesday, outta nowhere, the CEL (Check Engine Light) pops on while cruising. Seriously?! Grabbed a cheap code reader. Threw some weird code for the intake air temp sensor. Traced the wiring back near the airbox – looked fine visually. Unplugged the sensor itself, contacts looked clean. Still didn’t trust it. Bought a spare from a breaker’s yard just in case. Swapped it in – light went off immediately, stayed off. Sometimes, these old sensors just give up the ghost randomly. Annoying.
Big takeaways with this old beast?
- Heat melts wires (especially the regulator)
- Bad gas ruins carbs (clean ’em PROPERLY)
- Grooved clutch baskets cause havoc (inspect it when changing plates)
- Dirt under fork seals makes leaks (clean before you rebuild!)
- Sensors get flaky with age (have spares or be ready to hunt)
It ain’t perfect, but knowing what’ll bite you makes fixing it less scary. Older bikes are awesome, but man, you gotta keep on top of this stuff. That regulator heat issue though? Soooo common and dumb.
