Tech Questions & Answers | Shop Talk

Got a question? Try to stump Mark at

Tire Trauma
I just had an incident where my tire's valve stem cracked and the tire went flat. I had to ride on it for 3 to 5 miles to reach a safe area to stop, and then had the bike towed to the nearest open shop. They completely removed the tire, replaced the stem and reinstalled the old tire.I did this just to get the bike home since it was a Sunday, and the shop I normally use was closed. I didn't feel like the repaired tire was safe, so the next day I slowly rode to the shop where I bought my bike. They argued that the tire was safe, though they did replace the valve stem and supposedly check the tire to ensure it was safe before sending me on my way. Unfortunately, I still don't feel the tire is safe, and now the bike shakes more than usual. Is it accepted practice to remove and replace the same tire on a motorcycle more than once and would it be considered safe to drive on at any speed?
Ruben Sanchez
USAF Retired

I don’t have any problem with mounting and dismounting the same tire—I do it all the time on my dual sport bike, depending on where I plan to be riding, and no harm has ever come of it. However, whenever a tire is mounted, it should also be rebalanced, which I’m not sure yours was, and riding on a flat can cause hidden cord or bead damage as well. So for those reasons, along with the fact that you’re no longer comfortable riding on the tire, I’d suggest you replace it.

No Easy Answer
My 2001 Honda Shadow VT600C has developed an intermittent starting problem. The battery is fully charged, the starter operates normally, and the engine is getting fuel, but there is no hint of ignition in either cylinder. Sometimes a bit of persistence will get it to fire up, but usually it just cranks until the battery weakens. When I try again (from an hour to several days later) the bike starts just fine. No ignition problems are evident once the bike is actually running, and so far the problem has not occurred when the engine is warm.

Around the time the trouble began I discovered that the connector between the alternator and the rectifier had overheated and melted (allegedly common to many Hondas). I repaired the damage, but was left wondering if this may be related to my ignition issue.

Any ideas as to the most likely culprit?
Scott Guay
Oakland, ME

_Intermittent starting problems can be difficult to diagnose, and unfortunately, there is no easy solution. First verify that the engine is in fact getting fuel, and that the compression is good—your letter make no mention of how you’ve arrived at the conclusion that the ignition is the problem. I’ve seen everything from a bad spark plug to a sticky valve cause the problem you’re describing, so make certain that all your ducks are in a row before you condemn the ignition system and go off on a wild goose chase. _

_Assuming that the ignition is the problem, here’s how I’d proceed. With new plugs connected to the coils, (but not installed in the engine) and grounded to the block, crank the engine. You should see a fat blue spark jump the gap. If no spark is present, start by checking each ground and every connection in the ignition circuit; if nothing is found move onto the components. You’ll need a good digital ohmmeter and the Honda service manual, and the tests may not be conclusive, but they should at least help you narrow it down to the most likely suspect. _

_If spark is present, things become a little more complicated. Again, test your connections and grounds, and don’t be afraid to get a little tough with them—more than once I’ve traced an intermittent ignition problem to a loose connection that came and went as it pleased. Test all the components, paying particular attention to anything biased to one end of its specifications. _

Wide Wheel Warrior
I've just bought a 2003 Warrior and have a couple of questions. First, the rear wheel has been widened to 260mm. What tire pressure should I run now, and will the front pressure remain as standard?

Second, the bike has been fitted with Climax Control Systems handlebars, so the indicators only work when the button is held down. I've have been told you can get a relay to fix it, so that they will stay on until switched off. Do you know what relay I need?
Chris Seymour
Via email

I’d start by setting both tires to the stock (solo rider only) settings of 36 psi—front and rear. Ride the bike six to ten miles at a moderate speed and recheck the pressure. If the hot pressures have risen by 3-4 pounds, the starting pressure is right on the money and you’re good to go. If the pressure rise is 5 or 6 pounds, the tires were underinflated. Raise the cold pressure by 2 psi and recheck them. If there is no pressure rise or only a very small one, the cold pressure is too high, so reduce the initial setting by 2 psi. You can also reduce the tire manufacturer’s recommend maximum load setting by 10%, and then adjust the psi accordingly after you’ve ridden the bike.

As for your turn signals, I suggest you contact Badlands Motorcycle Products; ( they should be able to provide everything you need, including installation instructions. And yeah, it’s an easy job.