Suzuki Dragbike

[Herman T]

I found a video linked from this site to a GT380 with 3 into 1 exhaust on it. Having a 3 into 1 pipe on my dragbike currently and after seeing the comments on the video about this bike hitting 11,000 rpm I contacted the person who posted the video. He replied the next day and told me that the power band on his bike is between 6000 and 8500 rpm and the power slowly falls off after 8500 rpm and the bike will hit 11,000 rpm. Quite impressive for a 3 into 1 exhaust. Maybe there is hope for my exhaust setup afterall. Hopefully I will find that out this year. Right Hatchet and Richard?

http://www.youtube.com/watch?v=5Ik52cXFecg" onclick="window.open(this.href);return false;

[tz375]

As long as you don't rev the 750 to 11,000.

[Suzukidave]

As long as you don't rev the 750 to 11,000.

It will at least once

[Herman T]

I'm looking to get a tach for my dragbike. I found some mini ones on eBay that would be perfect for my bike if there is a way to hook it up. The auction states they are made for the old bikes. Only thing is, there is mention of a ratio and I have no idea what that is. 1:5, 1:7, 1:4 are the ratios offered in different auctions.. Which one do I get for my GT750? Here's one of the auctions.

http://www.ebay.com/itm/231024742247?ss" onclick="window.open(this.href);return false; ... 1423.l2649

[tz375]

Ignore all those cheap inaccurate mechanical tachos and go electronic. Or just get a shift light and don't bother with a tacho.

The ratio represents the gearing in a mechanical tach gearbox. So with 5:1, the motor turns 5 revolutions per single tacho cable revolution etc.

A Gt fires once per revolution on each cylinder.
4 stroke 4's typically fire once per revolution to fire a pair of cylinders.
Q.E.D. almost any old 4 stroke electronic tacho will work with a GT ignition system.

They are usually 3 wire. Power, coil signal and ground plus they usually have a lamp for night use. Wire the power lead to the power from your ignition switch. Wire the next lead to the side of the coil that connects to points (white, white/black or Black IIRC)
and the other to frame ground and you should be set.

Make a simple bracket and rubber foam mount the tacho to isolate it from vibration and you are good to go.

Here's one example http://www.ebay.com/itm/97-Suzuki-RF900 ... 57&vxp=mtr" onclick="window.open(this.href);return false;

[D&D CHASSIS]

as far as mechanical tachs go, 1:5 is Kawasaki and Yamaha.......1:4 is Suzuki and Honda.........

[Herman T]

Thanks for the info. I was also interested in a shift light but the one I was looking at, Kevin mentioned it was the wrong kind and wouldn't work with my setup. I think I should at least have a tach, considering I probably won't be starting out with an air shifter. I haven't even checked yet to see if the bike will shift. Haven't had it in gear yet. I better do that soon. I like the Vapor system also, being someone who is into gadgets but it might be a little too much to get that hooked up.

[old racer]

In all the years i raced my 750 and anything else for that matter,
I never used a Tach.

[Suzukidave]

Thanks for the info. I was also interested in a shift light but the one I was looking at, Kevin mentioned it was the wrong kind and wouldn't work with my setup. I think I should at least have a tach, considering I probably won't be starting out with an air shifter. I haven't even checked yet to see if the bike will shift. Haven't had it in gear yet. I better do that soon. I like the Vapor system also, being someone who is into gadgets but it might be a little too much to get that hooked up.

Not the drag racer , i would think something easy to see at a glance as everything happens quickly drag racing

[tz375]

Trail Tech Vapor is easy to wire up, but it's hard to read at speed and not as accurate as I would have liked. I have a huge POLARIS tacho that I'm sure would work off the alternator that I keep threatening to hook up just for amusement value.

Something like this http://www.protuninglab.com/5bl11krpmta ... 8283950120" onclick="window.open(this.href);return false; would be ideal if you know how to change it from 4 cylinder to single with wasted spark (ie two stroke).

Autometer do some wicked tachos but they cost an arm and a leg.

A shift light like this can work http://www.americanmuscle.com/msd-progr ... stall.html" onclick="window.open(this.href);return false;

OR get an RPM trigger switch - aka a window switch. It's a frequency counter I think, but electronic design is not my area of expertise.

[Herman T]

Would this work? It's cheap but really all that I want a tach for is consistency, seeing as how that is so important in Super Eliminator. I won't have an air shifter at first and I'm new to drag racing and figured a tach, even if it isn't spot on accurate certainly can't hurt. With some experience I'm sure I would be able to shift just from the sound.

http://www.ebay.com/itm/370882662493?ss ... 1423.l2649" onclick="window.open(this.href);return false;

[Suzukidave]

If it were me mounting a gauge that small i would position it so max desired rpm would have the needle straight up so at just a glance you could tell where you better make a shift up

[tz375]

I have no experience with that tacho but I would not expect it to be very accurate. But you never know til you try I guess

[Herman T]

I didn't realize how small that tach is until you mentioned it Dave. Less than 2 1/2" diameter. Small, that's for sure. I have to wonder how it would work for what I'm looking for. The needle might be so erratic that I wouldn't be any better off than I am without one. With what you guys have mentioned so far, I have to think that the best thing for me would be an accurate shift light. The cost for a good one might prohibit me from going that route. Not needing one immediately, maybe I can run across a good deal on one.

I better concentrate on getting the front brake setup completed. That's the last major task that has to be done to get the bike ready to race. I will keep my eyes open for a shift light. The one that was linked is probably too expensive but I will check into it more.

[D&D CHASSIS]

I have that same tach on my dragbike, and it`s not bad at all. Very steady, very smooth..........