Bench test motor

[socalrider]

anyone out there have an apparatus for bench testing motors? Care to show some pictures?
Gracias
Arnulfo

[1950Panhead]

JP sells a JIMS engine stand.
http://www.jpcycles.com/product/910-117" onclick="window.open(this.href);return false;
If you plan to run the engine you need to bolt the stand to a board, I-beam, etc.
You would also need a fuel tank on a stand (lawn mower tanks work good) and exhaust.
I have a Chevrolet stand I run engines on. I have found with panheads let the bike be the stand.
Jerry

[Robert Luland]

Easy pickings! Get a piece of 1/2" plate and weld a standard engine bench mount to it. Now get your hands on some 1.1/4"X1/4" square tube to weld up and over so you can mount a top motor mount in the right place. This will also give ya a place to mount the gas tank Jerry just mentioned. Remember the gravity thing when placing the tank. Now I know what you're thinking. Well how am I going to start it duuuud! Get yourself an old engine sprocket that fits your shaft and weld it to any shoot socket with a 3/4" drive. Pop on the impact wrench and it's fire in the hole. Don't forget to rig up an exhaust system going outside. As much as you might think your having fun, you'll really be dying. A car muffle with flex pipe will go a long way with keeping the locals off your back. Bob L

[drinner-okc]

If you do start it inside/stationary get a fan for airflow. Heat is a killer on a new tight engine. Especially if the carb is out of tune.

drinner

[Cotten]

Folks,

The conditions under which the first few billion revolutions for a fresh motor endures are critical for the quality of the rest of its life.

Our motors are designed to require a load.

Any "break-in" test bench should provide a realistic load, whether a calibrated water-brake dyno, or wedging a 2x4 board against rollers at the rear wheel (for hours).

Alternatives considered, it is most practical upon pavement.

....Cotten

[58flh]

COTTON beat me to it!!!--I type with 2 fingers --& yes you need a load on it instead of just freerun!--THIS is also how brake-HP is measured.--58flh

[jibhead]

i've been lead to beleive ,that an impact wrench on a motor sprocket will, ''shift the wheels'' i.e knock the flywheels out of true

[Bosheff]

jibhead, Please explain the rational for your previous statement. Seems to me it wouldn't make a difference if the engine was put in motion through a motor sprocket, which in turn spins the sprocket shaft, which in turn spins the wheels, or directly through the sprocket shaft with a nut or some other sort of coupler. I can't see where impact would be a contributing factor but I may/could be wrong. Someone please enlighten....bosheff

[58flh]

BOSHEF---The only way I can see it throwing it out of BALANCE say!----IF the nut was not tightened proper to begin with!--But even then, a stock motor should rollover & fire no problem!--I think anyway.--just my 2---I mean ive seen motors start like that before without any issues later-on.-OH yea I forgot to say I built my engine-stand out of heavy (unistrut)-welded to 1/2inch bottomplate/ & can be ADJ. for diff.motors easily by using (HALFIN ANCHORS)3/8-16-count on the HALFINS.--I even had my tranny in it!---BUT IM going to build another just for trannys!(good-luck)& wheels-up BO!--If you findout something we may have overlooked I would love to know!---Richie(58flh)

[Cotten]

Folks,

Given a big enough impact gun, anything can be broken.
Some flywheel assemblies are sensitive to shock, particularly modern forged wheels such as S&S.

Most starters of the sort we speak are not "impact" drivers, and have a sprague clutch to disengage it when the motor fires.

As far as balancing is concerned, if the motor is not secured as it would be in a frame, it is not balanced, no matter what you did to the wheels.

....Cotten

[jibhead]

as cotten said the 'impact shock' to the flywheels could/can 'knock' the wheels out off line ,thus unbalancing them . an electric motor with ratchet drive or sprague clutch would work much better.

you wouldnt catch me doing up or undoing a motor sprocket nut with an impact gun
regards jib

[Robert Luland]

I never had a 3/4" Impact ever start chatering. It's simply big enough to turn the engine with out that happening unless it has a weak clutch in it. I would not atempt it with a 1/2". It's just a quick and easy way to do it. You can rig up any thing you want if it turns the engine. If your that worried about. Weld the socket to a compensater. I never gave thought to anyone breaking in a motor on a stand. For me its just to test the engine, oil pump, carb, timing and shut it down. I didn't mention the fan because I felt that was a no brainer. Bob L

[Cotten]

Just for clarity, Folks,

A flywheel assembly skewed from true has its balance factor changed negligeably, but the bind and vibes from its loss of alignment can be dramatic, if not tragic.

A motor on the bench can be turned through quickly yet safely with a common "speed wrench":

SPDWRNCH.jpg (19.38 KiB) Viewed 2095 times

Oil can be circulated, and binds or interferences quickly detected, without danger.

....Cotten