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AdO650
24th November 2004, 20:21
Hi Everyone

What's the best way to undo, slacken off, remove the engine sprocket nut without breaking anything or getting a hernia.

any help greatly appreciated.

gordy
24th November 2004, 20:26
put the bike in gear, tap the nut with a hammer, then get the correct size socket and a large extension bar, use a sprocket wedge to stop it rotating(or anything else youcan jam in there) and one good heave should do it

gwcrim
24th November 2004, 20:29
I use a long tire jack tool and slide it through the wheel so that it's up agains the swingarm. Wrap it in a rag or something so it doesn't scratch the swingarm. Remember that it's left hand threaded.

AdO650
24th November 2004, 20:33
I thought the clutch was the leftie and the engine sprocket was normal, I read two manuals both didn't mention anything about engine sprocket being a leftie, besides on a wire wheel I think that method would result in bent spokes.
thanks anyway.

gwcrim
24th November 2004, 20:40
OOOOH! THAT engine sprocket....

Sorry... I was thinking of the transmission sprocket. :headb

For the engine sprocket I have used a piece of 2x2 1/8" aluminum sheet run up into the chain.

AdO650
24th November 2004, 20:41
Ok, Ok, sorry let me reiterate, I wasn't clear before..... The nut I want off is the Primary engine sprocket (the one that drives the primary chain) (crankshaft sprocket)...
thanks again..

gordy
24th November 2004, 20:43
ah right sorry cant help ya there never had mine off

AdO650
24th November 2004, 20:45
Riiiiight...!!! nothing can break that way then eh!! allyminimum wedged in the chain up to the sprocket..............and a BIG lever..... gottit
Thanks all

The Haynes manual said it would be tight. I didn't think it would be He-Man tight!!! :yikes

barry1967
24th November 2004, 21:40
Impact wrench works the best. Sorry I was late with the info.

flathead45
24th November 2004, 21:46
run a length of rope down the spark plug hole, not all the way in , just enuff to let the compresion squeeze the rope then slowly spin the motor till it locks , un do the nut then back the motor up to remove the rope

works to tighten the nut too

FastFwd
24th November 2004, 22:05
Great tip, Flathead. Thanks!

stevo
24th November 2004, 23:16
I use a 6" piece of old drive belt folded over and jammed in the chain/sprocket.

Depening on wether ya undoin or doin...it either goes against the front sprocket or the clutch basket.

You can use a rattle gun on later bikes BUT you are better off using a LOOOOOOng bar.

I've seen cranks twisted with a rattle gun....only 5 piece ones but still better safe than a rebuild


it's RIGHT hand thread...the clutch nut is LEFT hand

flathead45
25th November 2004, 15:26
crim , I've used it many times before , but I've used it on ironheads , never tryed it with evos
I would think that if it is done on the cylinder with the valves closed it would not be a problem

AdO650
25th November 2004, 20:53
Ok right here's an update.......
Thanks to flathead for reminding me about the Harley rope trick.... I remember seeing it somewhere....www.shakedown.d2g.com , HotXL pdf downloads.

Did it work..................no sorry, I don't think the big ring spanner I used was quite long enough, either that or I'm as weak as a kitten :o

The aluminium trick....... only managed to chew up a piece of ally, still no joy...

So what does a mech. fitter do when faced with a stuck nut, no workshop for miles...............at the other end of the plant (been there)........underground miles from the pit bottom workshop (been there too).........no air tools.........no hot spanner............So what do we do, we get the technical tackle out of the toolbox.........

Namely
1...2lb ball pein hammer.
1...cold chisel

And with a half dozen delft blows the seal was broken, but the fight wasn't over....nooo sir..... the damn thing was tight all the way to the end, did it squeal in protest with every grimace, every turn of the spanner like lesser nuts have in the past, noooo dear chums...... the surprise has yet to come ;)

After the battle I look in wonder at the amount of locktite on the threads.....Whaaaat!!!!! this guy must have used half a flamin' tube...... but what's this..... stamped on back of the alternator rotor...in letters 1 cm high
CAUTION - NO SHARP BLOWS

AWWwwwwww!!!!!!!...SHShshshylock
:eek: :eek: :eek:

anyway I got the nut off......I'll cross the other bridge (and see if the alternator is still workin') when I get to it.....


Bye now and see you in Whiney Gears
:tour

stevo
25th November 2004, 21:32
hope fully you havn't twisted the crank or dislodged the magnets

AdO650
25th November 2004, 22:07
You really know how to cheer a guy up!

stevo
25th November 2004, 22:13
I'm a trade qualified fitter and used ta work doin mining shutdowns...so I know how to get things apart...

BUT I've also seen a few twisted cranks and LOOOOOOTS of broken magnets with hammer marks on the housing.

With ya trade background I'd say ya have a better chance than most of no damage.

Whereabouts are ya??..I was born in Withernsea..

stevo
25th November 2004, 22:25
Just a point on the rope thing...you are more likely to twist a crank with the rope way than by putting rubber between the chain...
Th HD tool for that job is a stepped piece of rubber/urethene

The rope method means you are transfering force THRU the crank, the other way it's only if you are unlucky that you'll have a prob

AdO650
25th November 2004, 22:33
Well I've been in an' around Sheffield all my life, there's not much heavy industry now and I've been technically unemployed for a few years but I've become a carer for my wife Sue, who has MS, so you could say I'm not really unemployed..
BTW Sue's uncle has just moved up to Withernsea, thats just over the Humber from Cleethorpes (what a dump) isn't it..

Shu
25th November 2004, 22:58
I had the luck of having to fix a Fatboy (they are notorious for the compensator nut loosen up and then causing major destruction:) so for those who think the pre-02 sportsters leaky rocker covers were a problem, ask a Fatboy owner who lost his compensator nut:)). Anyway, I used a block of wook in the chain. Remember to clean up the threads on the nut and crank real good with something like brake clean , then use some red loctite and re-torque it correctly when putting it back together.

stevo
26th November 2004, 06:46
Yeah..I'm glad the olds moved over here...I went and visited in 97...what a dive.

They were born n raised in Doncaster

skooter
8th December 2004, 01:49
Watch one of those nuts turns one way and one turns the other. They are held in place with "lock tite permanent" and you have to heat the nut above 400 degrees farenheit before the lock tite will let go. To hold the sprockets and keep them from turning jam a block of wood between the primary chain and the clutch basket sprocket. These nuts are torqued on with about 165 ft lbs so get a long bar and watch your knuckles and don't loose your balance when the nut breaks loose.

The clutch hub has a left handed thread so turn this one clockwise to loosen. The engine sprocket nut has a right hand thread so turn this one counter clockwise to remove it.

You can use a propane soldering torch to heat the nuts to melt the lock tite. Make sure that you are aiming the flame at the nuts only!

Use Lock tite red "Permanent" to reinstall and retorgue these nuts properly or you will have problems of them coming loose.

The engine sprocket nut tightens to between 150 and 165 ft-lbs and the clutch basket nut tightens to 75 to 80 ft-lbs.

Good Luck

matt275
8th January 2005, 15:55
OK, got a question for everyone.. I have my engine sitting on a workbench, it had a new crankpin, bearings, rods installed.. now I have everything ready to go except the bolt on the crank. it says to tighten to 160 ft lbs !!!! Anyone have any ideas on how to install it when it stitting on the workbench ?

flathead45
8th January 2005, 16:42
go to the local pub buy the biggest meanest uglyest dude there a beer and tell him you need a table vice for about 10 minutes. then take him back to the bar and buy him a few more rounds ;)

Max Throttle
23rd January 2005, 12:15
i am about to face the same thing on my 80 ironhead replacing the primary chain and dont want to have to take the clutch apart to get the chain off

so in reading this i need to......

heat the bolt with the propane soldering torch.....

use a half in drive breaker bar......

on this front primary sprocket it's "left to loosen" (right hand thread........

block of wood or aluminum between the chain and clutch basket.......

be prepared to drop left nut trying to break it loose......

be ready to fall on my a$$ when it finally comes loose......

now

i take it i'll need a puller to get the sprocket off after the nut saga is over

and i'm hoping i have enough travel coming off the crank that the chain wont bind from twisting sideways getting the fron sprocket on and off

but it should all work....right?

AdO650
23rd January 2005, 13:19
Don't know about the ironhead setup, type to flathead45 about that..........but yeah that's about the size of it, you probably will have to take the clutch nut off as well to get the chain off and no the sprocket came off freely when the nut was off.................just like kids ain't they, little things causin' so much trouble :cry1

HrdlyDangrs
23rd January 2005, 13:24
OK, got a question for everyone.. I have my engine sitting on a workbench, it had a new crankpin, bearings, rods installed.. now I have everything ready to go except the bolt on the crank. it says to tighten to 160 ft lbs !!!! Anyone have any ideas on how to install it when it stitting on the workbench ?


Why do you feel it necassary to install the primary chain and clutch basket while the motor is on the bench??

I'LL SAY WHAT MY DAD WOULD SAY TO ME.....

WHAT THE HELL'S A MATTER WITH YOU>>>>WHEN THE HELL ARE YOU GOING
TO START DOING THINGS RIGHT>>>>GOD DAMMIT>>>>ALWAYS DOING
THINGS THE HARD WAY>>>>THERE'S NO WAY IN HELL YOU CAME FROM MY
LOINS>>>>I SWEAR YOUR THE MILKMANS BABY>>>>HONEY..YOU SEE WHAT
YOUR KID IS DOING>>>>HAND ME THAT WRENCH.....NO NOT THAT ONE...THAT ONE OVER THERE>>>>>>YOUR NEVER GONNA LEARN A GODDAMNED THING IF I KEEP DOING IT FOR YOU>>>>HOLD THE WRENCH HERE>>>>I'M GONNA HIT WITH THE BIG HAMMER !!!!

I would put the engine back into the frame and bolt it down. Then install your clutch basket, clutch, chain, sprocket,...install your nut and torque it down.

If you must do it on the bench, then I assume you went out and purchased a motor stand or made one. Bolt that stand down to the bench...which I'm sure is bolted down to the floor or wall studs......RIGHT??........NO???

WHAT THE HELL'S AMATTER WITH YOU>>>>>

Flamin883
23rd January 2005, 15:31
Max Throttle, try to heat the nut not the bolt as much as possible. the heat will expand the metaljust a bit loosening the threads a tad. but if you put the heat to the bolt not the nut you will expand the bolt tightening the threads.

HrdlyDangrs
23rd January 2005, 15:57
If you can stretch the primary chain enough to remove just the front engine sprocket, then you definitely will need a new chain or the chain just broke...

Removal of the front sprocket requires the removel of the clutch basket assembly also.

There is a tool that locks the front sprocket and rear clutch basket. They are cheap and well worth adding to your tool collection. Basically, its just two pieces of flat 1/8" bar stock. They have two holes drilled thru either end of the bars...but closer to the center. You put them together with a couple bolts and there are two metal collars that fit between the flat bars. You assemble it like a sandwich....stick it between the front and baskets rear teeth, then tighten down the two bolts...in effect bringing the two bars together. This keeps the two gears from turning.

YOU CAN MAKE THIS TOOL YOURSELF.....I DID.

Tool Part No. 97200-55 for 1976 and earlier....I'm sure HD makes one for the 77 and later Sportsies.


I am about to face the same thing on my 80 ironhead replacing the primary chain and dont want to have to take the clutch apart to get the chain off

so in reading this i need to......

heat the bolt with the propane soldering torch.....

use a half in drive breaker bar......

on this front primary sprocket it's "left to loosen" (right hand thread........

block of wood or aluminum between the chain and clutch basket.......

be prepared to drop left nut trying to break it loose......

be ready to fall on my a$$ when it finally comes loose......

now

i take it i'll need a puller to get the sprocket off after the nut saga is over

and i'm hoping i have enough travel coming off the crank that the chain wont bind from twisting sideways getting the fron sprocket on and off

but it should all work....right?

willprevale
23rd January 2005, 16:07
I'LL SAY WHAT MY DAD WOULD SAY TO ME.....

If we're gonna keep this guy around, I suggest someone post instructions on cleaning coffee outta the keyboard. :laugh

Thanks hrdly, for the memories of yesterday. Ya gotta great sense of humor :clap

Max Throttle
23rd January 2005, 21:17
i got that mo-fugger done!! :clap :smoke

thanks for the tips!!!

i heated the nut/bolt took a 1/2 inch drive breaker bar and took the handle off my floor jack and slid it over the breaker bar and put a little a$$ behind it, man that old breaker bar way beggin for mercy but it came loose with steady heavy pressure put on it

the old chain was so wore out it all came right apart, had to do some finessing to get the new one on but i got it :smoke

put a new carb on it to then did some adjusting with her running....well.....time to ride it!!

24 degree high today and some light snow on the ground.....screw it!! gotta ride it today so i suited up and took her for a spin!! :D

i got my baby back!! :tour

Max Throttle
23rd January 2005, 21:22
this is what i woke up to on my work jeep this morning but a man has to get a ride in when he can!! ;)

Gone
8th September 2006, 04:31
I have found 2 ways to get the pulley nut off:

1. Wait until you are on holiday in the middle of nowhere, a week after your warranty expires. Notice a worrying clonking coming from the primary that goes away when you let the clutch out in gear with the brakes on. Diagnose a loose pulley nut. Ride very slowly to a dealer who confirms it. "Common problem on that year. Didn't put enough thread lock on. Should have done a recall, but bad for PR. We've done loads. Costya £76."

2. Look in the workshop manual at the special tool, then make one. I used an old car tyre lever. Conveniently the same width as the sprockets, about 1/4 " thick and made of a material soft enough that it won't mark chrome, so should be OK on the gear teeth. Simply cut a length off that you can jam diagonally between the two pulleys (about 5"), and round off the ends a bit. You'll need to get someone to hold it in place (with pliers - mind fingers) while you heave on the longest breaker bar you can find. It's tight, but even I could undo it with a 2' bar, and I'm a bit weedy.

Absolutely, positively, DO NOT use ANY sort of impact. No hammering. No rattle guns. You WILL knock all the magnets off the alternator, and that will really spoil your day, and your transmission. I know. That's why I'm back in the primary again instead of riding...

Top tip from a professional engineer. ALWAYS pull the bar up, using your legs, not your back. If you push down and it slips, you'll smash your face on the cylinder head. Oh, and I can confirm that the MOTOR nut is right handed and the CLUTCH nut is the left hander. I did it this morning. Guess how I found out...

My only problem was finding a 1 1/8" long-reach socket in metric UK. If you don't have one, DO NOT try and use the nearest metric one, or a short reach. You will definately ruin the nut, and then you are in big trouble.

You'll need a big torque wrench to do this up. My biggest doesn't quite go high enough, so I have to let it break, then tweak it up a bit more! Horrible practice, but it's so tight it doesn't really matter.