I've not seen a thread like this specific to the ST1100 and thought it would be useful. I know this data is spread through various other threads, wikis and sites, but it would be nice to have in one concise location with at least the basics. I'll add my .02 and others can chime in as well. If it works out, I can summarize everyone's input into this first post, as time goes by. Owners manuals are attached to the bottom of this post. Please correct me as necessary.
Years Available: Europe: 1990-2000, North America: 1990-2002, police versions available through 2003.
- 1990-1995: 28A alternator (oil cooled)
- non-ABS with 2-pot brake calipers, 41mm forks
- ABSI with traction control and 2-pot brake calipers, 41mm forks
- 1996-2003: 40A alternator (air cooled)
- non-ABS: 2-pot brake calipers, 41mm forks
- ABSII: linked brakes, traction control and 3-pot brake calipers, 43mm forks, fork brace under the fender
- Keyed accessory circuit on the right side of the battery in a silicone sleeve.
- The ABSII dash is a little different... the blinkers are not in the upper light cluster, they are to the left and right of the speedo and tach
- ABSII models have two push buttons below the left cowl pocket. They turn off the ABS light (blinks when an ABS malfunction is detected) and turn off traction control.
- All years:
- 100HP
- 87 octane fuel, 7.4 gallon (28 liter) fuel tank.
- Front Tire:
- all non-ABS and ABSI: 110/80-18
- ABSII 120/70-18
- Rear Tire: 160/70-17
- Timing belt, as opposed to a timing chain. 90k mile Honda recommended belt replacement interval
ST1100 Info:
Recalls: Bank Angle Sensor, 1991-1993
Known issues specific to the ST1100:
- Swing arm rust in salty environments
- Final drive splines wear if not lubed/maintained properly
- 28A alternator leaks oil and/or quits charging
- The hose going from the thermostat housing to the overflow tank splits where it makes a sharp turn ~1" from the t'stat housing. This causes a leak of coolant and potential overheating.
- A few have had electrical issues, see Red Wire Bypass, Ignition Relay Bypass and Headlight Ground Circuit
- A very small few (including me) have had the tail frame crack. See this thread.
General Comments:
ST1100s are fairly bulletproof... they can easily go 200k miles with appropriate routine maintenance. There are numerous long-time ST1100 riders that are still around, so lots of experienced advice is available on
st-owners.com and
st-riders.net. Since these bikes have been around for so long, there's likely an
article or at least a discussion for most any repair and/or maintenance.
- Alternator: It's possible to upgrade the 28A alternator to the 40A, but parts, i.e. the base, are very hard to find. Take this into account if you're planning to purchase a 1995 or older ST1100.
- 1990-1995 had a 28A oil cooled alternator that had an oil cooler between oil filter and engine. This oil cooler was fed by coolant from the water pump.
- 1996 and up had a 40A air cooled alternator, resulting in no oil cooler and a different water pump.
- Valves: valve clearance should be checked, but generally don't need adjustment after the first time. They are relatively easy to check and adjust. There's a loaner kit available to aid in this.
- ABSII Combined/Linked (CBS/LBS) Brakes:
- The ABSII 3-pot linked braking system has much better braking power than any of the the 2-pot systems.
- Linked brakes are complex, have many hoses and are a little tricky to bleed, but they perform well and are very reliable as long as the hydraulic system is flushed and bled correctly and regularly.
- The front master cylinder activates the two outer pistons on the front calipers.
- The rear master cylinder activates the center piston on the front and rear calipers.
- There is a secondary master cylinder (SMC) on the front wheel. This is activated when the front brakes are applied, rotating the caliper assembly and thus activating the SMC. When the SMC is activated, the two outer pistons of the rear caliper are activated.
- This is the linked braking system for the ST1300, but it is very similar to the ST1100 ABSII system
- Clutch:
- It's normal for the clutch not to engage until the end of the lever release action, i.e. the last 25% or so.
- Clutch (plates) will last a long time, maybe 200k miles or more depending on use. The clutch hydraulic system should be flushed and bled regularly though.
- There is a bronze bushing in the clutch lever that wears. Should inspect and replace as necessary, maybe every few years depending on use.
- Timing Belt: There are no known timing belt failures due to age, most old ones come out looking/feeling new. Some have gone nearly 200k miles. Some have failed as a result of water pump and/or idler bearing failures.
- Tires:
- There are a few high mileage tires that fit the stock ST1100 rear wheel, i.e. a 160/70-17 Michelin Commander II/III
- There are some 'rear' tires that fit on the front wheel of the ST1100 for high mileage, i.e. a rear 110/80-18 Bridgestone BT45/46.
- Running a car tire on the rear requires an older Goldwing rear wheel and custom spacer. Therefore, it's not easy to go dark on an ST1100 compared to an FJR or ST13 where the stock rear wheel readily accepts a car tire.
- Rear Drive Splines: These are subject to wear and corrosion if not lubed properly and the (3) o-rings not replaced regularly. Use only moly paste, recommend Loctite 8012/51048.
- Fuel Shutoff Valve: A vacuum operated valve that closes (shuts off fuel) when the engine's not running... keeps fuel from leaking out if tipped over. The diaphragm can leak over time.
- Many owners bypass this valve to eliminate the risk of failure. It's done by removing the valve, re-plumbing the fuel line and capping the vacuum line it was connected to.
- Carburetor: there are four of them and they're pretty difficult to remove and re-install. They come out as a single unit. The rubber boots may need to be replaced as they get hard and brittle, along with the hoses and aluminum elbows/o-rings underneath the carbs. The carbs should be vacuum balanced when reinstalled.
- Most OEM parts are generally still available new. OEM body panels (tupperware) aren't available from Honda anymore.
- Gas Mileage: I've seen as low as 25 MPG with a strong headwind running at 80 mph and as high as 50 mpg. My average is 40-45 mpg combined city/highway.
- Fuel gauge: at 1/2 tank, you've used about 4 gallons. When the light comes on, you've used about 6 gallons, with 1.4 left.
- Temperature Gauge: Normally runs around the 1/4 point in clean air at speed, will hit 1/2 way (12 o'clock) in stop/go traffic and the fan comes on just past the 1/2 way point. When idling and stopped, i.e sitting in the garage, the fan should switch on/off every minute or two and temp shouldn't get more than 5/8 or so.
- Upgrades/Farkles:
- Most feel the OEM (or equivalent) maintenance parts are more than adequate, i.e. brake pads and filters.
- Many owners use iridium spark plugs for their longevity. NGK CR8EHIX-9 are popular.
- There's no significant performance gain with aftermarket air filters and/or exhaust. Some like aftermarket exhaust for their looks and sound.
- Suspension upgrades are generally perceived as a significant performance gain.
- LED headlights are also a significant performance gain in both seeing further and being seen sooner. H4 bulb Shimsare required to get the bulb tabs to line up.
- Note that both headlight bulbs are on for high and low beams
- Here is a list of all the LED bulbs you'll need to convert everything over to LED.
- Bar risers, windscreen and seat are the most popular and necessary comfort farkles.
- GPS, TPMS, LED spots, voltmeter, throttle lock/cruise control
Things to look at when buying an ST1100:
If you want an ST1100, my personal opinion is to buy a 1996 or later with ABSII brakes. ABSII models are hard to find, but IMO worth the wait and the few extra $$. If you don't want ABS or the linked brakes, at least get a 1996 or later to get the 40A alternator, which is more reliable than the 28A on the earlier models.
- History and maintenance records
- Condition and age of tires. Look at the date code
- Check VIN on bike and title to make sure they match. VIN is on steering stem.
- Brake and Clutch fluids should be pretty clear, not yellow. Pull the master cylinder covers to be sure, since the sight glass is often hazed.
- The brakes should firm up pretty well at about 1/2 lever travel.
- The clutch lever should provide resistance the whole travel. See note on clutch above.
- Pull the rear wheel and inspect splines. They shouldn't be worn much, and the paste shouldn't be dry.
- The rear wheel can be removed in less than 10 minutes while on the center stand, with only the panniers and rear mud guard removed. You'll need to swing up the caliper as well.
- Check the engine oil level (on centerstand) in the sight glass on the lower right side... there's a hole in the tupperware to see it, but will need a flashlight.
- Sit on it and bounce the rear up/down. It should settle in a couple bounces and not pogo. ST1100 rear shocks generally wear out in 50k-75k miles.
- Start it stone cold with the choke fully on. Should start right up and idle 2000-2500 RPMs. Adjust the choke and it should start to idle down.
- Once warm, go for a test ride, using the brakes pretty hard. After this, the bike should still roll easily in neutral, i.e. it should free roll backward on just a very slight incline. If it doesn't, suspect brake drag.
- After riding, let it sit and idle for a few minutes. The fan should come on at just over midpoint on the gauge. See temp gauge note above.
- On the centerstand, the rear wheel should rotate at least 1 turn freely when turned by hand.
- If ABSII (which has the SMC): On the centerstand, rotate the rear wheel and activate the SMC by hand (push up on the SMC) . The rear wheel should stop immediately and then rotate freely when the SMC is released. Rotating freely after release indicates that the SMC is not sticking.
