[lorddaftbiker]

I am running a bone stock 1998 T-Dub That I recently purchased. I parts cleaned the carb, reassembled it and the bike runs like Yamaha intended. It tops out at 65 and runs well. It can cruise comfortably at 55. I live in flat New Jersey and want to ride on the highway at 60 or better comfortably to get to the pine barrens (about a 30 minute ride). What is the best gearing setup to accomplish this goal? Should I put a bigger main jet in the carb? What say ye?



-Lorddaftbiker

 

[qwerty]

15T countershaft or 47T rear wheel sprocket, not both.



Refer to the thread on carb tuning pinned in the Technical Help forum. A 130 main jet is worth a try. It's what the rest of the word gets.

 

[lorddaftbiker]

15T countershaft or 47T rear wheel sprocket, not both.



Refer to the thread on carb tuning pinned in the Technical Help forum. A 130 main jet is worth a try. It's what the rest of the word gets.

Thanks, Querty. I've read your excellent carb tuning post, thank you for sharing. I have the old style carb, however, and the jets that guys say they're running are smaller. As I recall, you posted some part #s, so I'll give another look see and maybe try the next size up from stock.



Thanks again,

Lorddaftbiker

 

[qwerty]

Thanks, Querty. I've read your excellent carb tuning post, thank you for sharing. I have the old style carb, however, and the jets that guys say they're running are smaller. As I recall, you posted some part #s, so I'll give another look see and maybe try the next size up from stock.



Thanks again,

Lorddaftbiker

Yes, the early carbs used smaller jets. Try 2 sizes bigger than what is stock in a 49-state bike and that should be real close.

 

[lorddaftbiker]

Yes, the early carbs used smaller jets. Try 2 sizes bigger than what is stock in a 49-state bike and that should be real close.

Thanks again, will try 2 sizes up from stock, I have a 49 state bike. I should get to this mod in a few weeks, having too much fun riding the bike right now to take it apart again!



-Lorddaftbiker

 

[kj7687]

I for one WOULD do both (15 and 47), or a 44 tooth (same thing). IMO that is the optimal highway gearing for the TW - makes cruising at 60 a breeze.

 

[qwerty]

I for one WOULD do both (15 and 47), or a 44 tooth (same thing). IMO that is the optimal highway gearing for the TW - makes cruising at 60 a breeze.

I've run 15/47 and it was not good. Tough on the clutch when loaded or riding offroad. Plenty of times 4th gear would run faster than 5th gear due to wind or grade. Sometimes it worked, sometimes it didn't.

 

[capt hornblower]

I put on 15/49 and seem fairly pleased. Although I have not had enough experience on it to know what is best. It seems to have added about 6 to 8 mph, and gets me to cruising at 55 or 60 without running full throttle. Am now looking at options on carb to give it some more power.

 

[qwerty]

My experience is that 14/47 or 15/50 (your 15/49 is real close) is an excellent street and highway ratio, with redline about 80mph.



Stock sprockets are good for about 74mph at redline. The engine will generally pull that speed downhill or when drafting a cage. 14/45 and 15/47 are good for about 84mph at redline, but the engine won't pull that speed unless drafting, downhill, and with a tailwind. Note the difference between "and" and "or".



With stock sprockets, 1st gear is almost useless on the street, and 2nd is too tall for any practical acceleration from stopped. With 14/45 and 15/47 sprocket sets, 1st gear is much more user friendly on the street.



On the highway, stock sprockets are buzzy, but don't necessarily limit top speed because the engine will barely pull redline, anyway, unless some mitigating circumstance allows. 15/47 runs into situations where the bike won't pull 5th, so a downshift is necessary to maintain speed.



The 14/47 and 15/50 sprockets seem to be the best compromise between having a practical 1st gear and highway comfort and performance for most people. However, there are specific circumstances where a higher or lower ratio would be better. If one's street riding is in a mountainous area, and one's highways are generally lower speed, 2-lane, winding, and steep, stock sprockets will probably give the best all-around performance. If one's street riding is in a mountainous area, and one's highways are generally higher speed, 4-lane, and steep enough to need 4th gear going up, 14/45 or 15/47 sprockets will probably give the best all-around performance since the downshift would be required, anyway, and a hill that requires a downshift to ride up generally is steep enough to allow a TW to wind up to redline going down. TWs are great fun at 80+mph.

Another place a 14/45 or 15/47 sprocket set works well is if one rides urban expressways on a regular basis. Several strings of vehicles moving in parallel lanes has a significant effect on wind resistance. Tdub would actually cruise along at 70-75mph quiet easily in fast-moving traffic, once getting over the rpm gap of shifting to 5th. She wouldn't run 65 uphill, but she would run 75. Go figure.

 

[lorddaftbiker]

Great information, thank you for the replies. I took my T-Dub to the pine barrens via a 2 lane highway (with occasional passing lanes). It's about a half hour ride. The speed limit, which most folks exceed by 10 mph, is 55. But there's always some schlub who wants to do 55. When I found him, I just followed him at 55-60. The bike held that speed just fine w/the stock gears. Once in the pines, there's a lot of sugar sand that is anywhere from 3" to 100' deep. It sucks engine power and again, the stock gears seemed to work well. Most trails, whether two tracks or single track fire cuts through the trees, are a 20 mph or so proposition. I had a blast on some whoop-dee-doos that kept me standing on the pegs for what felt like miles.

I was in 2nd & third gear most of the time and the bike performed pretty well, even the suspension (although the banana I had in a bag on the rack got completely liquified by the time I drank it. The beef jerky was fine).



Given my needs - the combination of flat highway speeds & low speed sand slogging torque - I'm going to stick with the stock sprockets & chains for now. Higher gears would be fine for the flat highway, I'm sure, but I'd hate to make the little engine work too hard in the sand. Additional experience with this bike will guide future gearing choices.



Two other observations. On the highway, the T-Dub felt both exhiliarating and dicey at the same time. In the sand, the front end slides around a lot, leading to increased concentration and careful throttle modulation. It took hours before the smile left my face. This little bike is a hoot!

 

[qwerty]

Yes, the stock sprockets are a good compromise for most dualsport use.



Yes, the stock front tire sucks in sand and gravel.

 

[lorddaftbiker]

Qwerty,



Any insight on the front tire? Does a narrower front tire work better in deep sand? Does a balder tire work better? How 'bout lower air pressure than the factory recomendation of 18 p.s.i.?

 

[qwerty]

Qwerty,



Any insight on the front tire? Does a narrower front tire work better in deep sand? Does a balder tire work better? How 'bout lower air pressure than the factory recomendation of 18 p.s.i.?

A narrower tire acts like a rudder, a wider tire floats. TWs lack the power to push a rudder through sand. The stock front tread pattern sucks on sand. A more aggressive tread, such as the Kenda Trackmaster K760 rails on sand, but rides really weird on hard surfaces. Drop tire pressure down to about 12psi.



I suppose the bald tire question stems from sand rails running baldies. Sand rails are steered with brakes, not the front wheels. Not a good idea on a motorcycle.

 

[demarko69]

Qwerty,



Any insight on the front tire? Does a narrower front tire work better in deep sand? Does a balder tire work better? How 'bout lower air pressure than the factory recomendation of 18 p.s.i.?

heres ky kenda 270, 5.10wide loving it so far. (rear tire but mounted on tw front)

I will be spending several days on cinder'd forest roads and will report back

 

[RodneyReed]

heres ky kenda 270, 5.10wide loving it so far. (rear tire but mounted on tw front)

I will be spending several days on cinder'd forest roads and will report back

I've got the K270 5.10 as well. IMHO, it works better than the stock tire in every situation. The only downside is that it is 7 pounds heavier than the stocker. The upside to that is a heavier, thicker tire will usually hold up better in the event of a blowout.



Lordaftbiker: If dirt is your main game, I would go with the K760 Trakmaster that qwerty mentioned, but if you're talking 50/50 riding, the K270 is tough to beat.

 

[lorddaftbiker]

Qwerty, Demarko69, Rodney,



Thanks for the insight. I'm interested in improving performance in the N.J. Pine Barrens. I have to ride 25 minutes on asphalt to get there, but street performance is not what I'm seeking. When it's dry, the pine barrens has a lot of sugar sand that's a minimum of 4 inches deep. When it rains, the sand compacts and is much easier to ride on.



The consensus seems to be that guys are running wide front tires for most purposes, including deep sand. The T-Dub has limited power, so I guess that lifting the front wheel off the ground and steering with the rear is out of the question.

That would be a risky strategy anyway, b/c the trails are bordered by lots of pine trees. It makes sense that the best alternative to stock is a front tire that has a tread pattern that works in the sand...trial & error. I dig the look of that Kenda 270, gentlemen!



Time will tell, my brothers.



-Lorddaftbiker

 

[qwerty]

Kenda K270, IRC GP-1, and Shinko 244 all have a good rep on the front of a TW. Good on the pavement, good on the rocks, good on the hardpan, good on sand, good on mud. Not great anywhere, but better than a TW32 everywhere by a wide margin.