Tech Questions and Answers - Shop Talk

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No New Norton

Q

After reading the article on the Yamaha VMAX, I started wondering about a similar bike, the Norton 961 SS Commando. Norton refers to the bike as a

Sports Cruiser'. Heck, if it has

cruiser' in the description, I think it at least deserves a little `look see', don't you? So go drink a warm beer, put on your best Mac and find the bloke that sells' em. It could be more fun than fish and chips. Aye gov'ner.

Ron Rickers
Elk River MN

A Whether or not Norton's new owner Stuart Garner can revitalize the brand is highly debatable. If he can, it's more likely that the first bikes off the assembly will be rotary powered models similar to the last Commander and F1 models on which the former owners pinned so many of their hopes. In the meantime only two 961 Prototypes are in his hands and neither one is EPA/DOT or Euro-3 compliant so it's doubtful they'll becoming to any US showrooms in the foreseeable future. If they do rest assured I'll be one of the first in line to test them.

Back to school
Q I have been riding motorcycles on and off for the last 20 years. I have a 1985 Honda VF1100S V65 Sabre. I have always been interested in learning motorcycle mechanics and how to take care of them. I have read many books on the subject but have been too scared to try the hands on stuff. I have looked into courses/programs on the subject but there is nothing that is part-time and close enough to my town. Would you recommend those correspondence programs? Some people have suggested that I get a parts bike and a shop manual, and go to it. What would you recommend?
Raymond.
Alberta, Canada.

A It's my firm belief that God hates a coward, so my inclination is to suggest that you buy an inexpensive and easy to work on bike, perhaps a small single cylinder four stroke like a Honda XR 100 or something similar and rebuild it from stem to stern. I'd use the shop manual, and if I might immodestly suggest it, my own book; The Essential Guide to Motorcycle Maintenance as guides. I think you'd learn more that way than from those basic correspondence courses. However I once hired a guy that had graduated from a correspondence school as a mechanic and he turned out to be damn good one. Of course he now owns a hardware store, but I don't think that's in any way something you can blame on the correspondence courses he took.

Smells like?
Q I hope you can shed some light on my problem. I ride a 2006 Star Road Star with about 20,000 miles on it. At about 12,000 miles I had a set of Vance and Hines Powershots and a K&N; air filter installed. Per the factory specs, they rejetted the carb during the install. Right away I noticed a pronounced smell of fuel after parking that lingered for several hours. I took it back to the shop and they installed a smaller needle in the carb. However I am still getting the "too rich fuel smell". I have looked on several Road Star forums on the net and they say you should NOT rejet the carb but stick with the factory specs. I called Vance and Hines and they say they are following the recommendations of the manufacturer of the jet kit. By the way, I am also getting terrible gas mileage, at least by the standards I am reading on the forums for other Road Star owners. I hope you can give me some ideas of what may be going on.
Marty Bogenrief
Fort Myers, Florida

A All the indications point to overly rich jetting. Short of riding the bike it's hard to tell exactly where the problem lies, although my guess would be that either the pilot jet or the needle jet (if it was replaced) are too rich. But those are just guesses, the jetting might well be too rich across the board, or it might be something as minor as an incorrectly adjusted pilot screw. There's even a chance that the float level setting is off, or a vacuum or vent line pinched. I'd start the diagnostic process by determining exactly where the bike is running rich. If it's just at a particular throttle opening, try leaning out that carburetor circuit. If it's across the board, a return to the stock jetting might make it easier to fine tune things because you can change one jet at a time and see exactly how it affects the bike. Lastly, since most of your riding is probably at relatively small throttle openings the first place to start is at the pilot jet, try leaning it out with the mixture screw. If things change for the better you're on the right track.

Run Flat or not
Q I have 2 bikes, 1998 Valkyrie and 2004 FJR-1300 as well as a Reflex scooter. I wonder why motorcycle tire manufacturers don't make a run flat tire for bikes. I have them on my Corvette and I'm glad I do. Since bikes don't have spares either, wouldn't run flats be ideal? Has any tire company (Dunlop or Michelin for example) looked into this?
Tom Wright
Via e-mail

A Unfortunately, run-flat tires are not well suited to motorcycle use. There are two basic types run flat tires, the first Self Supporting Tires or SSTs use a very stiff sidewall to support themselves if they lose air pressure, and therein lays the problem. The stiff sidewall adds an enormous amount of weight to the tire, and it's all unsprung and rotational, so simply installing an SST would have a negative impact on handling and ride. SSTs are more expensive and tend to wear a bit quicker than a conventional tire, although I'll admit that not every user has found that to be true.

The second type of run flat is the auxiliary supported tire; these use a stiff inner ring to support the tire if air is lost. These tires require special rims and are very expensive and heavy, and fundamentally unsuitable for motorcycle use.

Currently there's not a huge demand for run-flat motorcycle tires. Down the road maybe, but given the lack of general interest, and the technical challenges involved in creating one I don't think it'll be anytime soon.