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Big G
10-27-2017, 02:38 PM
I figure it's about time I get my own torque wrench to work on my trikes. I'd like to just purchase one that will cover most bases for repairs on these machines. I'm thinking I need to consider the torque range (5 ft/lb - ???) rather then the drive size (3/8 vs 1/2). Just looking for some advise to steer me in the right direction. I also notice there is a digital adapter available to use with a standard ratchet. Not sure about these?...

christph
10-27-2017, 05:49 PM
With my machines--and I have quite a few--I've seen torque values from 12 ft/lb to 80 ft/lb. The lower values are for crankcase bolts, cylinder heads, etc., the the higher values are for suspension linkage. I think you'll be fine with 1/2 drive.

Aulbaugh
10-27-2017, 06:26 PM
a while back I picked up this 3/8 drive craftsman 5-80ft lbs. I like the digital display and the click when torque value is reached.

https://www.craftsman.com/products/craftsman-3-8-in-dr-digi-click-torque-wrench-5-80-ft-lbs

also I got this one that is shorter, 3/8 drive 4-44 ft lbs for tight areas. Also a digtal display but instead of the click it has a beep sound when tourque value is reached.

https://www.oreillyauto.com/detail/powertorque-tools-4691/tools---equipment-16488/tools-17919/hand-tools-16814/wrench-16658/torque-wrenches-18007/digital-torque-ratchet-handle/gm3110/4677064?q=digital+torque+wrench

El Camexican
10-27-2017, 06:45 PM
I don't use a tourqe wrench for anything under 10 pounds. I was taught as a kid that if you pull on a 3/8 ratchet with your arm straight your wrist will brake (bend) at about 9 pounds. It's never failed me and I've had people tell me I'm full of it and test the spark plugs I just tightened only to find out it was exactly 9 pounds.

The same trick works with T handled hex wrenches, your wrist brakes between 6 & 8 pounds, perfect for engine covers, but if you do opt to get a torque wrench for low poundage readings, get the kind that reads on a dial or flexible bar, not the clicker kind.

For the bigger stuff I use a 1/2" drive click style that I paid $10 bucks for about 30 years ago. For what I use it for I don't need a $200 Proto wrench, if it ever gets lost I'll be getting a new one at Harbor Freight. The accuracy of the wrench is far less important that the consistency. In other words when you are torquing a head down that calls for 35 foot pounds of torque, it is far less important that it is actually 35 pounds and not 36 or 33, what's important is that all the fasteners are all the same, so I'm good with my no name brand Taiwan tool.

Another little trick for nuts that you don't have an adapter for, like some cylinder nuts next to power valves and other obstructions is to set your torque wrench a few pounds under the final number you are looking for and tighten one of the e accessible nuts and then take the same ranch that you were planning to use to get at the hard-to-reach nut, get comfortable and try to tighten the nut just a little bit more and note how much force you had to put on it. Then try to get into the same position and bring that hard to get nut to the same tightness. Then go finish torquing the nuts that you can reach with the wrench and come back to that hard to get to nut and tighten it roughly the same degrees of revolution that the other nuts required in order to achieve the desired rating. I've done this on dozens of engines and never had an issue come up from it.

Also make sure you work your way up when torquing nuts and bolts don't go straight to the torque rating you're looking to achieve, first snug everything up by hand nicely and then start going around and bringing the fasteners up about 10 pounds at a time until you get to the desired number.

Oil, anti-seize and thread locker can make things turn easier, particularly anti-seize. Be careful when using it, especially with aluminum.

Shawn Powell
10-27-2017, 08:51 PM
I have three. 1/4” 3/8” and 1/2” I use the 1/4” the most for the dirt bikes. Worth all the pennies. Especially if you get into engine rebuilds.


Sent from my iPhone using Tapatalk

350for350
10-27-2017, 09:02 PM
I don't know about the digital ones, but on the others, always back the wrench off all the way before storing. If you leave it set, it can throw the readings off. I had a machine shop tell me that. They weren't into power sports, but did rebuild all kinds of automotive engines from stock to at least one NHRA Pro Stock dragster engine. I assume that this advice would apply here too.

El Camexican
10-27-2017, 10:03 PM
I don't know about the digital ones, but on the others, always back the wrench off all the way before storing. If you leave it set, it can throw the readings off. I had a machine shop tell me that. They weren't into power sports, but did rebuild all kinds of automotive engines from stock to at least one NHRA Pro Stock dragster engine. I assume that this advice would apply here too.

Yep, always back them off after use. Now an NHRA Pro Stock dragster engine is something I'd like to see.

HairyJR
10-28-2017, 12:11 AM
Even with top quality tool manufactures the accuracy is +/- 10%. Where I worked we used certified calibrated torque analyzers and pulled all our torque wrenches setting too required torque valves. The torque valves are not generally set to fastener or material yield strength but to a valve not to distort. There torque manuals for dry or lubricated treads, you need to know as there's a difference. I'll add one other not well known fact for torquing those hard to reach fasteners, you can use a crow's foot at a 90 degree angle to the wrench, "right angle" ( not straight out ) and it gives you the same torque valve as a socket. My personal torque wrenches are inch/foot 1/4 & 3/8" drives.

"HJ" 247331 :beer

El Camexican
10-28-2017, 06:53 AM
Hairy, have you ever heard anything to the effect of having to set your wrench tension higher when using extension bars? A trained mechanic once told me there was a formula that for every inch of extension you had to set the wrench X amount higher to allow for flex in the extension. I had trouble believing it then as I do now, but thought I'd ask.

HairyJR
10-28-2017, 11:23 AM
Nico there's a complete science world around tighten, torque, thread enbeddment and or stretch of fasteners. You are correct in there's a loss in extensions, very small amount I don't remember the value as we pulled all our wrenches on analyzers to the required valve with all attachments ie sockets, extensions, crows foot....
All metals move, the extensions twist as torque is applied, think of it like the needle torque bar wrench, why does the needle move? Bar flex. They are the best wrench for applying even torque to all fasteners. Even with a torque wrench value set using a torque analyzer the difference between a 120 lb person or a 250 lb person applying that torque actually is different.

"HJ" 247336 :beer

El Camexican
10-28-2017, 11:58 AM
Makes sense, thanks!

I think this also (at least in the case of our bikes and trikes) reenforces my belife that uniformity on something like a cylinder head is more important that acheaving an exact torque value. Of course in the case of a fitting on a jet engine, or steam boiler it would become a lot more important.

Ol Deuce
10-28-2017, 10:11 PM
A 3/8'' is all I need!!!!:Bounce:Bounce:Bounce:wondering Ol Deuce

HairyJR
10-28-2017, 11:19 PM
The question to always consider is "tighten or torque". Most people over tighten as they use a larger wrench/handle which applies additional torque leverage to the material/fastener stripping or breaking both. Head gaskets are generally torqued to compress gasket/fiber/metal for proper seal along with not warping. I only torque a couple items on all my bikes, head gasket, top cam cover, stator rotor on crankshaft to pull it up on the tapper and maybe the clutch nut.

Back to the OP's original question, buy an inch/lb torque wrench (has fine adjustment) that starts at zero as your 5 lb torque is 60 inch/lbs.

"HJ" 247348 :beer

Big G
10-30-2017, 12:30 PM
Thanks everyone for your tips and feedback. I'm gonna start off with a 3/8" drive as I think this will cover most of the basic stuff while working on these machines. Hoping to find a digital style as mentioned, however our options here in Canada seem to be more limited then the endless supply of product you guys have down in the States! Ha ha

BarnBoy
10-31-2017, 04:36 PM
Big G, I see you are in Canada. Swing by your local NAPA auto parts (Should be one in Vancouver right?) and check out their UltraPro Torque wrenches. About $90 a piece, give or take. I have 2, one in 1/2 and one in 3/8. I think the 3/8 goes from 5 ft lbs to 80 ft lbs, and the 1/2 goes from 30ish ft lbs to 150 ft lbs.

They are pretty good quality, and have a screw so you can re-calibrate them yourself if they ever get off. I have had them for a few years and have had no problems. NAPA warranty is pretty good too.

As mentioned previously, BACK OFF THE WRENCH ONCE YOU ARE DONE!! It will seriously affect the torque readings. The non-electronic torque wrenches are perfect for anything you will use. No real advantage to having an electronic torque wrench. And there is a battery to die, a screen to break, electronics inside, etc. And, for $100, you will probably get a pretty crappy electronic wrench, whereas with the click type $100 will get you a very good quality wrench that will last you a long long time.

keister
11-01-2017, 12:35 PM
My elbow clicks at 5 newton-meters and then again at every 5 n-m interval until my shoulder pops out of joint at 100.

But seriously, I got a $50 Craftsman 3/8" drive model about 20 years ago. It has handled every trike job I've ever needed. Only thing it doesn't do is go high enough for my truck lug nuts. Mine can be set at 1 ft-lb intervals.

The beauty of ATCs is that in the manual, it always give s a torque range (19-24 fps, for example), so you don't have to get them perfect. Just somewhere within the range. I normally err to the low side since I have a tendency to overtighten and strip. A cheap Harbour Frieght (or Canadian Tire) tool should serve you just fine.

Also worth restating, back it the whole way off to zero to completely unload the spring tension after each use. This is a safety concern too.

Big G
11-01-2017, 03:07 PM
Thanks again guys. Good tips, especially about backing off and resetting to zero. Keister I'm surprised you know about Canadian Tire! ha ha

keister
11-02-2017, 10:42 AM
Thanks again guys. Good tips, especially about backing off and resetting to zero. Keister I'm surprised you know about Canadian Tire! ha ha

I have lots of Canadian friends - most of whom I met on this site. I also know about Kraft Dinner, chip nuts, and panzerotti.