Please Educate me on the Mk2 Isolastic
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swooshdave said:
When it comes to turning wrenches that profanity dictionary is always by my side. I like to see how many combinations of my favorites I can string together at a time. The neighbors know when its time to just drive by and not look me in the eyes. Unfortunately my wife still hasn't figured it out!
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They were designed and meant to be adjustable but bean counters killed that. Its such a booger to use shims it take self injury and bike scuffing to adjust so tend to just go to slope so its a no brainer to spend and do it now and enjoy for ever more the fine tuning that about as easy as spark plug change if ya count getting the spark plug and tools out too. Main issue is the adjusting peg and holes tend to bend and wallow out if frame binding against their spread. A more robust adjust method/tool would be nice.
Must research and graphing by experts all tend to aim for the softest at front that still do the job.
Must research and graphing by experts all tend to aim for the softest at front that still do the job.
Ron L
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No, it's just a matter of taking a little length off the tube. Anyone with a lathe can do it.
As for shimming originals, it's not that bad once you get the hang of it. In fact the front is dead simple and usually needs more attention than the rear.
I have a mix on my bikes, some have vernier front and rear, one still has all shims, and one has a vernier rear and shim front. Just make sure you use the bronze impregnated teflon washers and not the crappy red or black nylon ones.
DogT
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Yes, the front one is easy to do if you take it off. The rear one is another story, but if you have the cradle out it's just as easy. You might want to look up that thread on the washers. Not everyone sells the good ones and there's a lot of junk out there.
Go here and read it about 10 times and you may start to understand it. Once you get into it, it's apparent what is going on.
http://www.members.shaw.ca/randell/
Dave
69S
Go here and read it about 10 times and you may start to understand it. Once you get into it, it's apparent what is going on.
http://www.members.shaw.ca/randell/
Dave
69S
Hey I really appreciate everyones input on this topic.
I can definitely see the merits of the veneer style adjuster over shims if adjustment to the Iso's is required. Especially once everything is off the work bench and installed. I am not afraid of the shimming but I do realize it can be a PITA, and requires stocking shims.
I understand the possible modifications needed to the front Iso mount, and that the modification is not necessary with certain styles of venire adjusters.
The headsteady is another issue and I'll read through the former threads before asking any more.
I think the only area that I would like to hear more on is the choice of Iso's. Dave said he liked the MK2 over the MK3, Hobart modified his, some of you think the MK3 are fine. I know this is vary subjective but are their any iso's, either by brand or style, that you either love or hate!
I can definitely see the merits of the veneer style adjuster over shims if adjustment to the Iso's is required. Especially once everything is off the work bench and installed. I am not afraid of the shimming but I do realize it can be a PITA, and requires stocking shims.
I understand the possible modifications needed to the front Iso mount, and that the modification is not necessary with certain styles of venire adjusters.
The headsteady is another issue and I'll read through the former threads before asking any more.
I think the only area that I would like to hear more on is the choice of Iso's. Dave said he liked the MK2 over the MK3, Hobart modified his, some of you think the MK3 are fine. I know this is vary subjective but are their any iso's, either by brand or style, that you either love or hate!
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Mike Randall's iso article is mis-guided, the isolastic system is a TWO point system and the headsteady a mere scabbed on after thought. If the head steady is made to be part of triangled iso support then Vibration city is you home. Norton found adding any more rubber or tougher rubber transmitted vibes above desired threshold. I just repeated and verified above on Trixie feeling undue vibes after setting gap on the bench, looked straight to the head steady to find its mount bend and straining the rubbers. Crow bar and sledge hammer and anvil fixed that and blunted nicely the vibes still getting through and found most of that was dang old worn rear tractor cleat tire.
Also Mike is mis-guided in where the iso motion is pivoting, it ain't the front that is for sure! The front bounces up/dn from pistons, and side to side frond the rear tire patch leverage and also twisted by front-rear tire direction conflicts. In case you ain't noticed counter steering points front to outside of turn to lean the rear into the turn so cycle can turn. The front tire does not turn a bike only the rear does. The front is only a rudder action to aim the rear and I and many stunt riders and unicyclers' know you don't need no stinking front tire in traction to turn sharp as you like, if you have stable enough chassis to get away with it, which an unlinked Cdo sure ain't.
At least Mike is the only other one I know that knows the front down tubes act like torsion bar when the front is aimed one way and the rear the other and that minor mis-alignment of mounts and frame is total non issue to handling if can assemble w/o too much brute force with only side effect being annoying vibration when loaded leaned. What I may be the only one to know is the front mount tabs twist the frame tubes and spring back. Only a silly mm or less but turn your fork a mm at hwy speed and see how un-silly that matters.
My blunt conclusion is bean counters cut the full design of Roadhoders and isolastic linkage and only thing you can do staying in Norton camp is get a smooth cruiser that better not try to follow modern sport bikes into fast sweepers.
Ms Pee has left the Norton and modern world behind in both total disappearing vibe act and un known limits to corner ability by simple triangulated linkage so can set isolastics looser than factory but not too loose I found as chassis twist and rebound hits again.
I am stuck in Norton camp with Trixie Combat to fine tune like all the frustrated rest of ya, trying to test my own skills and to have honest example of what can be done for comparison with what is Flabbergastingly Fabulous.
Also Mike is mis-guided in where the iso motion is pivoting, it ain't the front that is for sure! The front bounces up/dn from pistons, and side to side frond the rear tire patch leverage and also twisted by front-rear tire direction conflicts. In case you ain't noticed counter steering points front to outside of turn to lean the rear into the turn so cycle can turn. The front tire does not turn a bike only the rear does. The front is only a rudder action to aim the rear and I and many stunt riders and unicyclers' know you don't need no stinking front tire in traction to turn sharp as you like, if you have stable enough chassis to get away with it, which an unlinked Cdo sure ain't.
At least Mike is the only other one I know that knows the front down tubes act like torsion bar when the front is aimed one way and the rear the other and that minor mis-alignment of mounts and frame is total non issue to handling if can assemble w/o too much brute force with only side effect being annoying vibration when loaded leaned. What I may be the only one to know is the front mount tabs twist the frame tubes and spring back. Only a silly mm or less but turn your fork a mm at hwy speed and see how un-silly that matters.
My blunt conclusion is bean counters cut the full design of Roadhoders and isolastic linkage and only thing you can do staying in Norton camp is get a smooth cruiser that better not try to follow modern sport bikes into fast sweepers.
Ms Pee has left the Norton and modern world behind in both total disappearing vibe act and un known limits to corner ability by simple triangulated linkage so can set isolastics looser than factory but not too loose I found as chassis twist and rebound hits again.
I am stuck in Norton camp with Trixie Combat to fine tune like all the frustrated rest of ya, trying to test my own skills and to have honest example of what can be done for comparison with what is Flabbergastingly Fabulous.
rvich
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When I put my 750 back on the road I used the original set up and bought shims. My reasons where:
1.) I didn't want to spend a bunch of money on adjusters when I still wasn't sure how much money I needed for other stuff.
2.) I didn't want to do modifications to the bike until I had enough experience with the stock set up to bitch about it in a knowledable fashion.
3.) I hoped that with more experience I would be a better prepared to decide which type of modification suited me.
I bought rubbers from Old Britts. Because of other threads ongoing at that time I checked them to see if the were soft. They seemed to be. I put them in and have been riding around in blissful ignorance of what I missed out on by buying the upgrade.
The biggest difference in handling on my bike to date, swingarm clamps, and shocks. The difference was , well, shocking!
Russ
1.) I didn't want to spend a bunch of money on adjusters when I still wasn't sure how much money I needed for other stuff.
2.) I didn't want to do modifications to the bike until I had enough experience with the stock set up to bitch about it in a knowledable fashion.
3.) I hoped that with more experience I would be a better prepared to decide which type of modification suited me.
I bought rubbers from Old Britts. Because of other threads ongoing at that time I checked them to see if the were soft. They seemed to be. I put them in and have been riding around in blissful ignorance of what I missed out on by buying the upgrade.
The biggest difference in handling on my bike to date, swingarm clamps, and shocks. The difference was , well, shocking!
Russ
rvich said:
Russ,
Vary solid reasoning, especially 2.) & 3.), behind your choices.
I am looking at acquiring parts at this stage. My hope is that I'll make good choices that will serve me for some time. Considering my last road ride was more than thirty years ago, I no longer have the experience to make comparisons. I am also trying to stay away from some of the big modifications to protect the budjet. You know, I am really happy that you and the other good folks out there are willing to tell me what is working for them.
DogT
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That's pretty much what I did. The only thing that didn't work as original was the capacitor so it won't start without a battery. I put the shims in figuring at some point if I want, I'll buy Hemmings adjusters. Same with the points, I did buy a Pazon, and am considering the Sparx hi output rotor and stator, and a belt drive, but I have a while to decide on that, I'm just getting lots of little items squared away first on the shakedown cruzes, like oil leaks (got 2 fixed, working on the breather), sticky shifting (fixed), just doing a bit at a time and 20 mile rides. You could spend lots of money up front, but it's enough just getting it going unless you know you want all that extra stuff and can afford it. At least it helps spreading the money out a bit at a time and it keeps me busy.
Dave
69S
Dave
69S
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Id found 2 1/2 to 4 1/2 thou clearance good , by 5 though the precission was going at speed , KR 76 Fr K 81 R .
2 though and she'd bind a bit but free of in a few days . 10 thou was wander city .
Was std. 2A spec 750 , dunno if anyone else would agree ?
2 though and she'd bind a bit but free of in a few days . 10 thou was wander city .
Was std. 2A spec 750 , dunno if anyone else would agree ?
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I agree its a trial error compromise to get as smooth as can be and still feel secure as can be even on tri-linked Peel. Traditionally they had to pay people to ride Cdo's with isolatics set for best handling, ie: police, racers and test riders. Even though they didn't get paid much don't mean they they didn't have to endure much vibration to better handle the turning in Jolly Ole England.
I finally have a factory runner after 3 yr's w/o so had to put up with a modern V-twin road buzz appliance that wasn't too hard to decide to just take a cage and coffee and stereo instead, but it did hold the road better than any un-tamed smoothee could. I've finally put Trixie's road tool kit together to start playing with front and rear gaps on the hwy. Trixie is calming down already into acceptable hum vibration, after new rear tire. Last pm I found loose bolt on upper LH Z-plate, so hope that is what I was feeling.
Peel's rod links are mounted rather far from the isolastics so didn't really keep them from clashing just bouncing back at me when under severe changing loads of lumpy surface, throttle spikes and cuts and shifts mid turns to keep from over rev'ing. If I put Peel much under factory she buzzed and if I got much over factory she tended to hinge and I chickened out wisely, never ever to enter hinged handling states pushing my luck and reflexes again. That is for paid factory testers, racers and police and those crazier than me.
I finally have a factory runner after 3 yr's w/o so had to put up with a modern V-twin road buzz appliance that wasn't too hard to decide to just take a cage and coffee and stereo instead, but it did hold the road better than any un-tamed smoothee could. I've finally put Trixie's road tool kit together to start playing with front and rear gaps on the hwy. Trixie is calming down already into acceptable hum vibration, after new rear tire. Last pm I found loose bolt on upper LH Z-plate, so hope that is what I was feeling.
Peel's rod links are mounted rather far from the isolastics so didn't really keep them from clashing just bouncing back at me when under severe changing loads of lumpy surface, throttle spikes and cuts and shifts mid turns to keep from over rev'ing. If I put Peel much under factory she buzzed and if I got much over factory she tended to hinge and I chickened out wisely, never ever to enter hinged handling states pushing my luck and reflexes again. That is for paid factory testers, racers and police and those crazier than me.
grandpaul
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Re: Please Educate me on the worls of Mk2 Isolastic
I don't know who told you it's not, but it is.
Technically, "isolastic" is norton's trademarked name for it's 3-point rubber isolasted anti-vibration system. Those three points are front, rear & top.
The vernier adjustable kit that I sell is drop-in for either the earlier or later MkIII front mounting tube.
I persoanlly like the taylor top steady very well.
I also highly recommend Windy Eads' front steady.
DonOR said:
I don't know who told you it's not, but it is.
Technically, "isolastic" is norton's trademarked name for it's 3-point rubber isolasted anti-vibration system. Those three points are front, rear & top.
The vernier adjustable kit that I sell is drop-in for either the earlier or later MkIII front mounting tube.
I persoanlly like the taylor top steady very well.
I also highly recommend Windy Eads' front steady.
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Ugh, technically the rubber cushion in between two studs is known as a Lord's isolator mount as they invented it IIRC. Those were and have been used widely long before Norton came up with their "isolastic" mount, which does not at all resemble or function like mere muffler hanger Lords mount. Further the head steady should not be a static load bearing element but isolastics are. Also if and when more rubber area or less soft rubber fitted as part of load bearing component then the vibration isolation threshold both raises and its isolation effectiveness decreases.
Lastly the good reports on non rubber non isolating rod link head steadies feeling better than factory Lords mount also votes against the factory version or rod as any way a proper Commando Isolastic. A 3rd real isolastic at top has fallen out of favor, guess why or just ask around.
If ya ask this place for a 5/16" isolastic mount they will just go huh, must be another Brit bike shopper... But the Harley vendors will know want ya mean.
http://www.aircraftspruce.com/menus/ep/ ... 0lord.html
LORD RUBBER ENGINE MOUNT
Lastly the good reports on non rubber non isolating rod link head steadies feeling better than factory Lords mount also votes against the factory version or rod as any way a proper Commando Isolastic. A 3rd real isolastic at top has fallen out of favor, guess why or just ask around.
If ya ask this place for a 5/16" isolastic mount they will just go huh, must be another Brit bike shopper... But the Harley vendors will know want ya mean.
http://www.aircraftspruce.com/menus/ep/ ... 0lord.html
LORD RUBBER ENGINE MOUNT
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