The Honda VFR800 is the evolved and further realized rendition of the legendary VFR750.
The VFR800 is a luxurious all-rounder, handling nimble enough for inner-city rip-roaring and dressed, bagged, and comfortable enough for long-distance road-running.
Some of these steak-and-tater 800s are coming up on being 20 years old; its cult following claims it holds its own against anything else out there, but what are the common problems with the Honda VFR800?
Kick back and read on, Motor and Wheels did all the investigatin’ for ya!
1. Regulator/Rectifier Wears Early
The Regulator/Rectifier on any bike is bound to need replacement, eventually. That said, in our research, we found the most common complaint about the VFR800 to be regarding the early failure of its Regulator/Rectifier.
The Regulator/Rectifier is vital to a functional VFR800’s charging procedure. Let’s look at how the component functions and cover some VFR800 R/R troubleshooting data.
How a Regulator/Rectifier Works on a Honda VFR800
Any moto with a battery, including the Honda VFR800, employs a course system to charge the battery during operation.
A fundamental charging system element is the Regulator/Rectifier.
As the name implies, the Regulator/Rectifier on a Honda VFR800 rectifies the AC power produced by the stator coil by transforming it to DC power, employing it to re-charge the battery.
The Regulator/Rectifier also manages, or regulates, the power output—the R/R also stops your battery from incurring damage or bursting by keeping the power surge within the 14.5-volt range needed by your battery.
Causes of Regulator/Rectifier Failure on a Honda VFR800
There are many potential contributors to Regulator/Rectifier delinquency, the most common being heat.
- Honda’s Regulator/Rectifiers haven’t always been the most equipped to bear the heat rendered by the VFR800’s four-valve power-house of a motor.
- Some condemn the virtue of the component itself. At the same time, others look to Honda’s R/R positioning on the VFR800, theorizing that the placement puts the part in a heat-focused area without abundant airflow.
Eventually, a Regulator/Rectifier that overheats frequently is destined to wear out.
- Another possible cause of R/R destruction is a malfunctioning battery.
- Sometimes a battery can malfunction due to temperamental connections.
- Other times, R/R might fail simply because the battery is old and weak, and the interaction is harmful.
Symptoms of a Failing Regulator/Rectifier on a Honda VFR800
There are two broad patterns that a Regulator/Rectifier exhibits when failing on a VFR800.
If the diode burns out, your VFR800’s battery will deplete, forcing all the usual bad battery symptoms to manifest—
- Dimming headlights
- Fluctuating readings
- Hard starting
- VFR800 won’t start at all
The first thing to test your charging system with a voltmeter, starting with the battery. Then, move onto the R/R itself.
How to Test Your Honda VFR800’s Regulator/Rectifier
Observe these steps to test your Honda VFR800’s Regulator/Rectifier:
- Detach your Honda VFR800’s wires.
- Adjust your multimeter to the diode setting.
- To check your rectifier, connect the positive lead into your VFR800’s positive diode and hook the multimeter’s negative lead to the VFR800’s stator inputs. There should be no readings.
- Attach the VFR800’s positive diode to your multimeter’s negative lead and your positive lead to the VFR800’s stator. The meter should trigger a reading; the number isn’t relevant yet. Repeat for the negative diode by hooking the meter’s positive lead up to VFR800’s negative diode and the negative lead to VFR800’s stator input. Once again, the meter shouldn’t reveal any numbers when you hook up the positive lead and stator inputs.
- Now, inspect the VFR800’s regulator by connecting the meter leads up to your Honda VFR800’s battery while it’s idling. You’re looking for numbers lower than 14.5 volts but higher than 13.5 volts. If the reading is more elevated, your VFR’s battery has overcharged. If it’s less, your battery isn’t getting sufficient charge. Either way, it’s likely time to replace your Regulator/Rectifier.
Fortunately, replacing your R/R eight with a new and more resilient one is a concise job for any reputable home mechanic. If not, Honda technicians are more than familiar with the infamous problems and solutions of the R/Rs on many models, unfortunately including the VFR800.
2. Failing Cam Chain Tensioner
The next most commonly encountered issue among Honda VFR800 owners is the rapid wear and tear of the cruise-bagger’s Automatic Cam Chain Tensioner.
Rather than employing an iteration of the manually adjustable tensioners used on other makes and models, various early Honda models, including the VFR800, equipped an automatic cam chain tensioner.
Honda developed the VFR800’s Cam Chain Tensioner (CCT) to acclimate itself automatically to the fluctuations in the cam chains, adjusting the chain in real-time.
To understand how an automatic cam chain tensioner fails, let’s begin with how a Cam Chain Tensioner works on a Honda VFR800:
Your Honda VFR800’s timing chain connects its motor crankshaft and its camshafts, so they turn in a mighty unison with each other, compensating the timing between the pistons and valves, so the engine functions in unity.
- As its name suggests, the Cam Chain Tensioner is contrived to preserve the timing chain at its spec stress.
- As we noted earlier, while some bikes employ a manually modifiable CCT, the VFR800 uses a mechanical tensioner.
- A correctly working mechanical tensioner is convenient unless it fails to tauten the chain automatically like it’s intended to.
- If it fails to tighten the fluctuating cam chain to spec, an auto cam-chain tensioner is not only useless; many of them can’t be adjusted by hand.
When slackened, the chain beats about, potentially rendering some wear to nearby parts.
There is inconvenient wear and tear, but a slapping cam chain creates a horrendous rattling noise along the way.
Fixes for a Broken OEM Automatic Cam Chain Tensioner on a Honda VFR800
Miscellaneous aftermarket Cam Chain Tensioners are out there, each intended to replace the factory part on a specific Honda make and model, including many options for the VFR800. Here’re ways to repair a failing CCT on a Honda VFR800:
- Your VFR800 came fitted with an automatic mechanically adjusting CCT. You can eradicate any potential problems by hooking your VFR up with a manual adjuster.
- Installing a manually modifiable CCT lets you eradicate any slack by setting the timing chain tension at a typical spec throughout the RPM range.
- More than a handful of Honda home-technicians I’ve encountered believe a manual CCT is safer, more dependable, and more responsive since the valve timing will always be factual.
It’s vital to explore numerous options to ensure you purchase a tensioner that fits your VFR800 and make sure it’s built from a quality alloy.
That way, you don’t have to concern yourself with striping threads during installation.
A quality aftermarket cam chain tensioner tends to weigh less than the Honda adjusters, lightening your load just a hair.
A well-made manual CCT should arrive with clear installation instructions.
That said, there’s no shame in utilizing a trained Honda tech to find out what Cam Chain Tensioner is suitable for your VFR800. It’s a common issue on multiple Honda models—an experienced Honda technician has dealt with CCT replacements for years; I’m sure they’ll be delighted to suggest a few choice options for quick and easy installation, either by you or by them.
The result will be a more assured cam chain experience.
3. Thermostat Stuck Open
Another common issue expressed by Honda VFR800 users in the forums and identifiably a few consumer studies is an improperly functioning thermostat; namely, the thermostat gets stuck opened.
Here’s an example of a real-life scenario from a Honda VFR800 ower who had their bike’s thermostat stuck open:
On one of my last rides of last season, I noticed that my engine temperature wasn’t rising past 150°F or so at idle and would drop to 120-140° when cruising. Granted, ambient temperature at the time was approximately 35°F, but just idling it should have crept up much hotter. Regular operating temp for my bike when cruising was ~170-190°F. Clear indication of a stuck open thermostat.
- When the thermostat is functioning correctly, it should be shut when the engine temperature is 0° to 170°F. At this temperature, the thermostat is sealed to prevent coolant flow to the radiators and permit the motor to warm up.
- At 170°F, the thermostat commences opening, permitting the coolant from the VFR800’s radiators to begin cooling the motor by dispersing the coolant therein.
- Then, the system flows the hot coolant back to the radiators, where it re-cools the coolant to continue the process.
If the thermostat gets stuck in the opened position, the cold coolant constantly circulates, never permitting the bike’s engine to get up to temperature.
Honda goes into more depth about this process in the VFR’800’s service manual, somewhere around pages 6-8.
Note: Always consult the service manual, available online or via Honda, during repairs. In this case, the VFR800’s service manual provides detailed function and repair data with pictures and diagrams to get the thermostat repair task knocked out with minimal stress.
Besides, there are a few different online guides spread around the forums with better pictures and, in some cases, video coverage.
Poke around Google for quick and straightforward descriptions of how the thermostat functions and what to do when it gets stuck opened.
Between the VFR800’s Service Manual and various online media walkthroughs, fixing a stuck therm is an effortless procedure for anyone who can twist a wrench, including home-mechanic trainees like yourself.
Don’t rush yourself. Keep your tools and hardware organized, label where electrical connectors came off, and keep careful track of parts and bolts.
Worst-case scenario, it’s a quick and straightforward job for any decent Honda-literate moto-mechanic; it won’t be more than parts and an hour-an hour and a half or so of labor if it’s just a quick thermostat replacement.
General Pros and Cons For Honda VFR800
Here’re some pros and cons of the Honda VFR800:
- The V-four motor delivers silky power through the entire gear spectrum.
- The VFR800 is a bike that functions well for commuting, joyriding, or long, precise tours.
- Comfortable seat and riding position.
- The VFR800 might seem heavy when you’re sitting still; once you hit the pavement, the handling gets smooth, and the low center of gravity evaporates the seemingly heavy weight.
- The VFR800’s legendary handling, suspension, and engine performance make it fun to ride.
- Failing Cam Chain Tensioner
- Regulator/Rectifier Wears Early
- Thermostat Stuck Open
What Do the Reviews Say?
The VTEC model’s even more reliable. Three problems each affected 5% of owners; thermostat issues, alternator burning out and cam chain tensioner failure. They’re all pretty rare but be wary of the cam chain problem – one owner paid just under £1000 to have the resultant damage fixed on his 32,500 mile 2003 VTEC A3 model. There were five other one off problems, all minor.
Overall the VFR800 is one of the most reliable bikes we’ve surveyed especially considering many are getting old. Buy and ride one with confidence. If you do want more information on the few known problems as well as loads more great VFR info, check outhttps://www.visordown.com/reviews/used-bike/buyer-guide-honda-vfr800
What’s the Resale Value of a Honda VFR800?