How many miles from an FZ1?
I have owned my 2006 Yamaha FZ1 since new, and it’s been ridden in every state west of the Rockies including British Columbia, Yukon, and Alaska. It’s quick and comfortable and in short has been the best motorcycle I’ve ever owned. The odometer this past weekend clicked over the 70,000-mile mark. It still runs like new and I hope to get another year out of it, but the clock is ticking. I don’t think I’ll have the funds for a new one in that time. Since the model is essentially unchanged would I be foolish to have the engine overhauled? Who would you recommend to do it?
It depends on how you’ve ridden it of course, but the FZ1 motor is under-stressed compared to its original use in the R1 and should have a longer lifespan than 70,000 miles. As long as it’s not burning oil, making any funny sounds or showing signs of metal in the oil, you could potentially get quite a few more miles out of your bike before a rebuild. You can have a compression test or leak-down test done to check how things are sealing in the combustion chamber, and you can also have the oil analyzed for any signs of wear. That will give you a good idea of what’s going on inside. When it does come time to do something, it may be cheaper to get a low-mileage engine from a wreck and do a straight swap. If you decide to overhaul the engine, paying full-pop for a dealer to do everything will be quite expensive. Ask around and try to find a mechanic or race engine builder that will do it on the side, and do as much as you can — like removing and installing the engine — yourself.
Ducati Damping Dilemma
I’ve had a Ducati ST4s for about 2 years now. I weigh 225 pounds, so I re-sprung the stock forks and stock Öhlins rear shock for my weight. The rear end and shock ride fine and the bike handles well. Now the problem: No matter what I do, the front end rides harsh through potholes or I feel a slight jackhammer effect through the handlebars on uneven pavement. I’ve had the bike and forks to three shops, including one that specializes in setting up racing suspension, trying to correct this problem. All the front-end components including wheels and tires have been checked. The Showa forks have been torn down, inspected and reassembled by different mechanics. All agree the new fork springs are right for my weight, not binding, etc. The forks have good seals, all fork interior components are in good shape and the shops each serviced the forks with fresh stock weight fork oil up to stock levels. We’ve re-adjusted all the variables — preload, compression and rebound — numerous ways trying to dial this harsh ride out. I primarily do about 40 percent street riding with 60 percent canyon riding. I’m really not interested in spending $1000+ on exotic fork suspension hardware to correct this issue as truthfully, my riding is not up to that level yet. I recently posted this problem on the Ducati.MS website. Another ST owner wrote me saying he was a comparable weight and had the same problem. He corrected it by dropping the fork oil level one inch in each leg, increasing the fork’s air chamber. The owner said this eliminated the fork harshness, giving him a plusher ride. He said the front end still handled well with the reduced fork oil levels. I would really like to get your thoughts on what my suspension problem might be.
Chula Vista, CA
If you have the right springs for your weight, changing the air gap in the forks will most likely not help much with the symptoms you describe. You can sometimes change fork oil level to mask too-soft or too-hard springs for a given rider, but once you have the right springs you would only change the oil height to alter how the suspension reacts when it’s close to bottoming. Still, it’s an easy enough change to try. Use a rear stand and support the front end using a jack stand under the engine. Carefully (!) remove the fork caps and let the front end compress so the springs are showing. Use a syringe and small tube to take out some oil. You won’t be able to measure the height inside the fork, but you can remove a siphon-full, put some of that into a cup and return the leftover. You want to take out 15-20ml from each fork tube at a step, about one shot if you’re into cocktails.
Generally a harsh feeling in the suspension, or the “jackhammer” feeling, is from too much high-speed damping, and that is why you can’t tune it out using the stock adjustments. Using a lighter fluid will help, although that will have a broad effect and change other things you don’t want affected. Ideally, you should change the valving inside the cartridge, either by using Race Tech Gold Valves or by having the forks re-valved by another company. The Race Tech parts are nice in that you can do the install yourself and save some money. You’ll need a good selection of tools and some patience, but it’s usually not too difficult with Showa parts. One other thing to look at is the front tire. A particularly stiff or overinflated tire will transmit more bumps more than you want. If you have never changed tires, that would be another good thing to try before diving into the suspension. On a bike like the ST4 we would use 32 psi in the front tire for no passenger/no luggage sport riding. SR
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