Tactical Shifting

[Sidewinder Jerry]

An item which will greatly improve the riding experience for shift kits is a tachometer. This item can also help single gear ratio riders as well. For shift kits: engines have a max horse power at a certain rpm. You can then be in a gear which hovers around that range. This way you'll know if you need to be in a higher or lower gear. For single gear ratios it can help keep you from over revving your engine; such as when you're going down hill.

The tachometer/ hour counter I use you can get from Staton Inc or Northern Tools. It cost around $50. It is a simple device which has a wire that wraps around the spark plug wire. The hour counter is helpful for knowing when to clean the air filter. For 4 strokes its good for knowing when to do an oil change as well.

 

[butre]

tachs are fluff if you can hear your engine, shift with your ears. if you don't know if you're over revving based on the sound you won't know based on a number.

 

[Sidewinder Jerry]

Well good for you if you can hear the difference between say 6000 and 7000 rpm. I'm probably among the many who can't. Also you really didn't mention the hour counter. The RS 35 recommends cleaning the air filter every 8 hours and changing the oil every 50 hours. I'm not gifted enough to remember from day to day how much time my bike ran.

Being in to high of a gear puts strain on the engine and being in to low of a gear can lead to over revving. This is an inexpensive device which can prolong the life of the engines for us normal people. The 4 stroke engines have stats at what rpm they produce max horse power and what their max rpm is. To me seeing you're in the right gear is better than guessing. Tachs are fluff tell that to a NASCAR driver or any type of racing vehicle driver for that matter which rely on their tach for shift points.

 

[butre]

I just think it's one of the last things I'd be spending money on.

 

[Fabian]

tachs are fluff if you can hear your engine, shift with your ears. if you don't know if you're over revving based on the sound you won't know based on a number.

On the face of it, i would agree with you (if not knowing anything about these motorized bicycle kits) but i rely on my tachometer to prevent the engine over revving. This might sound absurd for someone who has traveled over 55,000 kilometers (34,000 miles) on a motorized bicycle (fitted with a shift kit), but the difference between 4,800 rpm and 5,100 rpm isn't great, and it's easy to exceed 4,800 rpm if not looking at the tachometer, especially in "low ratio crawler gears".
Considering the big end connecting rod bearing has significantly reduced life if revved over 4,800 rpm, i'm always looking at my tachometer when squeezing max power out of the engine, or just holding a gear because the gradient is too steep to change to the next fastest ratio.

Even in normal riding conditions, i'm always looking at the tachometer to make sure the engine is sitting somewhere between 3,500 and 3,800 rpm when needing to stay in the maximum torque band.

I'll freely admit, that i feel completely lost if the tachometer isn't working.
Of course, i can ride the bike without a tachometer, but you'd be surprised at how much more efficiently you can ride if using a tacho to keep the engine is spinning at the perfect rpm for the situation at hand.

 

[Sidewinder Jerry]

Fabian you're pointing out the difference between experienced riders and inexperienced riders. Like you I live in a mountainous area. Fortunately for me my bike shifts automatically. But like you said being in the wrong gear coming up a 20-30% grade hill could spell disaster. Another thing going down long steep hills can quickly having you over reviving its easy to get caught up in the excitement of a high speed. Mountain riding is a whole diffent beast. Flat landers don't understand this until they've ridden here for the first time.


Does yours have an hour counter?

Still the tach I'm talking about is $50 and will prolong the life of a $400 engine. To me that more than pays for itself. I've found by listening to those who came before me, it's possible to avoid their mistakes. This is known as wisdom.

 

[Fabian]

This is my solution, with any bicycle speedo able to record accrued hours:

http://www.motoredbikes.com/showthread.php?23281-Motorised-Bicycle-Tacho-Super-Simple-amp-low-cost&highlight=super+simple+bicycle+tacho

 

[Sidewinder Jerry]

That's really cool. I've seen some of the bicycle computers for as little as $12. Another $5 or less at Radio Shack and you have a tachometer and hour counter for less than $20.

The only advantage the one I use over your setup is I don't need a battery and I get an engine idle rpm. Being able to set the idle can be a big gas saver.

 

[Fabian]

The only advantage the one I use over your setup is I don't need a battery and I get an engine idle rpm.

You do present an accurate assessment of the situation.

 

[Sidewinder Jerry]

Its wet here today my friend. So ride for me if you can.