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mowisme
12-15-2012, 11:09 AM
Hi folks- I posted while back on differant issues on this GX620- and thanks to all the help it seems to be running great. I don't want to over-rev it but at same time want the max safe rpm. Is their any way I can check rpm without the crank exposed? Not sure what to buy or even how to hook up a electronic tach? Years ago I had a dwell meter..didn't they show rpm's? - my mind is fuzzy on this as I never had reason to check rpms before. Any thoughts on a tach from HF? Thanks again- Gene

BigFish
12-15-2012, 11:37 AM
Forget the dwell meter. HF sells a tach-DVOM for cheap. I have no idea how good it is, but if your only needin it this one time, why not.

They make a Tiny Tach that's not too expensive, but I understand the knock-off versions aren't very accurate.

Most mechanics nowadays use a good digital tachometer that you only have to get the unit near the plug wire for it to pick up a pulse. Some can be pricey.

Oldtimer
12-15-2012, 12:33 PM
BRIGGS & STRATTON Engine 800-50,000 RPM Vibra Tach/ Tachometer 19200

http://www.iskco.com/iskco_web_2012_035.htm

No batteries--no LED displays.

Oldtimer

BigFish
12-15-2012, 12:41 PM
BRIGGS & STRATTON Engine 800-50,000 RPM Vibra Tach/ Tachometer 19200

http://www.iskco.com/iskco_web_2012_035.htm

No batteries--no LED displays.

Oldtimer

Yeah, and a pain in the a$$ to use!

I got two of em, ya wanna buy one.......or both!

261914

261915

ricky86
12-15-2012, 01:54 PM
BRIGGS & STRATTON Engine 800-50,000 RPM Vibra Tach/ Tachometer 19200

http://www.iskco.com/iskco_web_2012_035.htm

No batteries--no LED displays.

Oldtimer

Those Vibra-tachs are incredibly accurate. Does require some practice, but far from difficult to use.

BigFish
12-15-2012, 02:09 PM
Those Vibra-tachs are incredibly accurate. Does require some practice, but far from difficult to use.

OK, I'll trade ya my TWO, count em, TWO treysits for your digital hand held tach!

piston slapper
12-15-2012, 02:43 PM
OK, I'll trade ya my TWO, count em, TWO treysits for your digital hand held tach!

He's serious....I am now the proud owner of a nice pair of Polish verneers...
Formerly owned by the BigFish himself...only cost me a RATchete...circa 1857...

dutch1
12-15-2012, 03:19 PM
Here's what I've used since the mid 90's--tough to beat for the money.

http://www.amickssuperstore.com/OPPAMA_PET_1100_Tachometer_p/oppama%20pet-1100%20tach.htm

I picked mine up at an Echo update where they were selling them for around $50 bucks as I recall. They are still available from Echo. About 3-4 months ago, mine would read 2X the actual rpms and I contemplated buying a new one. An Echo dealer quoted me $120, but a battery replacement took care of the problem. I have an Echo part number if anyone has an interest.

BigFish
12-15-2012, 09:41 PM
Yeah, I use a similar one from Oppama via Echo. Mine doesn't have all the buttons though.
The dam thing is thin as could be and works great.

BigFish
12-15-2012, 10:00 PM
Yeah, I use a similar one from Oppama via Echo. Mine doesn't have all the buttons though.
The dam thing is thin as could be and works great.
Mine is a PET 1000R Echo part # 99051130017.

The PET 1100R is Echo part # 99051130018.

They are the hot lick!

ricky86
12-16-2012, 03:19 AM
I might take you up on that. I got one the kid hooked up to a bare plug terminal. Might need a little recalibration. My point is, they are very accurate and a cheap alternative to a quality digital.

Richard Martin
12-16-2012, 08:23 AM
If mowisme was going to be a small engine mechanic I can see spending big bucks on a tach. But he's not. A low dollar Briggs, Sendec or TinyTach is all he needs for this one time chore. 50 or even 100 RPM of inaccuracy isn't going to make any difference.

I've tested multiple "cheap" tachs side by side before and if they're inaccurate, then they're all inaccurate by the same amount because they all said the same thing.

mowisme, if the tach you buy has options as to spark, you want the wasted spark version. Although your engine is a 4 stroke it is still firing the plug on every revolution. That's why it's called wasted spark.

mowisme
12-16-2012, 08:40 AM
thanks folks on all the input. Richard is right..I'll use it this one time and then it will sit in the never ending collection of 'this-n-that' storage bin. Thanks on the direction to go here..I'll see what I can come up with that is fairly cheap but yet will get me in the ball park. I see we have a new 'Northern tool' store open here..I'll start there. Gene

BigFish
12-16-2012, 11:36 AM
Hey fuzzy-mind, just drag it down to the local mechanic and have them set it. Most applications and most all small engines call for a top speed of 3400-3600.

mowisme
12-16-2012, 02:56 PM
fuzzy mind?..you mind to explain BF?.. or is that just your personality? If latter Then Gosh- better cook them their fish little better. But hey- I do respect your mechanical skills but might want to work on the social skills (kidding)- loading it up and taking it in to garage and forking out $45-$65 to do a 2 minute check not really practical. This isn't no 'small town' spot on the map here..all about money here at these places. If it means loosing a $1000 motor-yes..But I'll buy a tach and save the motor.

BigFish
12-16-2012, 06:46 PM
Hi folks- I posted while back on differant issues on this GX620- and thanks to all the help it seems to be running great. I don't want to over-rev it but at same time want the max safe rpm. Is their any way I can check rpm without the crank exposed? Not sure what to buy or even how to hook up a electronic tach? Years ago I had a dwell meter..didn't they show rpm's? - my mind is fuzzy on this as I never had reason to check rpms before. Any thoughts on a tach from HF? Thanks again-
Gene

'Nuff said????

mowisme
12-16-2012, 07:45 PM
My oppoligies BF- I thought You was calling me names to be a a@*se.. But you are telling it exackly as it is! Fuzzy for sure on past. shoot..I need to go bury my head now. I guess I need to put more thought to my post and be bit more open minded- Thanks on explamation. Gene

BigFish
12-16-2012, 08:28 PM
Another option is to check your local Craig's List. Should be a number of small engine mechanics, prolly find some mobile ones also. I advertise my services on CL.
I specialize in remedial social skills!!!!!!!

mowisme
12-16-2012, 09:22 PM
Thats good one!..Yes , CL is another good option. Thanks