Norton Roadholder modifications (2009)

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norbsa48503 said:
John, What oil did you end up using? Kinda nice to get off cheap once in a while aye?
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10 wt Motul synthetic; it's what I had on the shelf. Since I weigh 270, I already had heavy springs in there and I drilled the damper tubes to a full 1/4", the 10wt seems to be about right. I could experiment but sheesh, I've got enough projects . . . . although I did feel an occasional chatter while under heavy trail braking. Could be tire pressure, could be damping.

Yes, your kit is a true value. Didn't get my act organized to buy the "no leak" seals but took comfort from Jim Schmidt's comment about their greater "stiction" and re-used the old seals. No leaks. Had to "train" my old squashed gaiters/bellows to stretch themselves out, to their new longer length while on the center stand, with zip ties and a bit of glue.
 
hobot said:
Hehe, yep exactly what i discovered, plus more lean before fouling. If ya don't have a fork brace yet, there is more fork joy yet to come. I find myself reflexly shifting back and down before attacking corners with Greg's kit, makes me feel like a hillbilly hill climber rather than road racer but the G's are so sweet I don't care.

Might try plain ole power steering fluid some time.
Click to expand...

She does have a fork brace, one that I made out of two upside down "U" shaped pieces of round steel tube many years ago.

I knew that I was going to be riding higher speed roads with my liter bike pals so I did start the day off by raising the tire pressures by 2 pounds at each end. So that puts doubt in my mind - did the higher pressure bring on the chatter? or is the fork oil too thin or too thick? If adjusting tire pressure back down doesn't cure the chatter (it only happened twice in the course of a 200 mile day's 75 or 100 miles of twisties), then I might try a different weight. I'm wondering, however, which way to go. That is, just what does chatter, in terms of dampening, indicate? thinner or thicker?
 
xback > "chatter" ?? Hm. What do you mean? How did you induce it?


Ok got a robust brace, which I find don't really stop fork twisting so much as stiffen them up to oscillate above tire grip frequencies. I can sort of induce 'chatter' on far over sharp turns but finally tracked it down to the slack in top bushes, found by light push-pull at axle when forked unloaded full extension. New bronze bushes were even looser so kept the 40 yr old ones, so far. No effect on handling security. When hard over on power the front gets so light it may be scrubbing more. I do sense it could resonate in some condition to help tire let go so would like to experiment with tighter or different contour bushes. So far I have been unable to do much of a turn and keep the forks from unloading. Put a foot rest cross your brace and tell me what facts you find.

If your 'chatter' is dampening related and occurring when forks most unloaded by bike mass and traction and you have stouter than average springs, I'd guess thicker fluid but hey its your hide pressing Cdo or any bikes handling quirks.

Alas until you do skip or wiggle out, ya don't really know the instant limits.
Ugh - like a moth to a flame.
 
What I describe as chatter is when I'm turning, trail braking, and the front tire is loaded near the limit and it slips/bites/slips/bites at a high frequency.
 
Ugh, ok, i think trail braking is the number one worse condition of control and traction there is for any motorcycle. But if that's conditions, then forks are more compressed-forced to follow road texture, which is desirable, so maybe less damping for faster following might extend anti-chatter loading zone.

The Gravel forced on me a reflex that hits my R palm/fingers like grabbing a red hot bar of metal to grip it when leaned. The Gravel has taught me that when traction is the least to only do one pure max control input at a time, braking hard only straight up is at top of my list. Trail braking is best way I know to induce a low side off at the tangent. If you can creep up on trusting rear grip only, that sense of unloading the forks for easier turning can pay back in road orgasms. I think of forks as merely a rudder that is used to turn a boat or plane, rubber is too small an area to turn the craft but does turn the craft itself to present a larger surface to effect the turn. I just use forks to help assist the rear aim or get out it out of the way of rear aiming when it can't help any more.

BTW if you ever do wash out the front, say crossing unseen grit or such, a quick hard stab of the rear brake can jerk up to get both tires in line for some serious braking till ya can get back in line or lane. Sometimes its too fast to react too.
 
Hi, I am in the process of modifying my forks to get the increased travel and noticed it looks like the holes you drilled in the damper are smaller than original, can you advise on how many holes and what diameter?

Thanks
 
ludwig said:
A worthwile mod is to no longer fix the damper rod in the top nut , but let it sit on the spring , and limit fork travel by using a longer top bushing or a spacer below the bushing . 2 - 4 cm , depending on how much travel you want .
This will solve the problem of centering the rod and make fork maintenance like oil change , setting ride height ..soo much easier , because top nuts can be removed seperately :
Norton Roadholder modifications (2009)


Norton Roadholder modifications (2009)


Nice one Ludwig!
How do you secure that threaded nylon top?
Your bike on the avatar does not have a centre stand, using this mod a centre stand probably won't function anymore.
Click to expand...
 
Ludwig wrote:
New damper caps are nice , but on rebound , far more oil escapes downwards past the floating piston ( cup ) , wich has a clearance of 0.35 mm ( 0.015" ) .
You could consider making pistons with less clearance .

1) understood. How much less clearance and what oil is used? Have you done this to satisfaction?

Ludwig wrote:
In a STD roadholder , compression damping is almost non existent .
The squared off washer allows too much oil flow .
IMO, Improving the damping is more rewarding than increasing travel ..

2) again understood. Is compression damping desireable?

BTW that is a crafty bit of thinking with the floating plastic spring bush, was it noisy, I mean could the spring extension keep up with the fork tube action over say some surface resembling a freeway chatter strip?

Thanks in advance for response (from anyone).
 
AntrimMan said:
Ludwig wrote:
New damper caps are nice , but on rebound , far more oil escapes downwards past the floating piston ( cup ) , wich has a clearance of 0.35 mm ( 0.015" ) .
You could consider making pistons with less clearance .

1) understood. How much less clearance and what oil is used? Have you done this to satisfaction?

Ludwig wrote:
In a STD roadholder , compression damping is almost non existent .
The squared off washer allows too much oil flow .
IMO, Improving the damping is more rewarding than increasing travel ..

2) again understood. Is compression damping desireable?

BTW that is a crafty bit of thinking with the floating plastic spring bush, was it noisy, I mean could the spring extension keep up with the fork tube action over say some surface resembling a freeway chatter strip?

Thanks in advance for response (from anyone).
Click to expand...

Unfortunately, Ludwig has stopped posting on this forum, but you can take what he wrote as a starting point and try to make the modifications for yourself.

Jean
 
daveh said:
Jeandr said:
Unfortunately, Ludwig has stopped posting on this forum

Jean
Click to expand...

Do you know why?
Click to expand...

Hi Daveh,

Below is a footnote at the end of Ludwigs Alpine roads thread. If you haven't read the thread make yourself some time and a coffee and enjoy. :D


"footnote :
This is my post # 1000 .
I promised myself not to go over that limit .
Altough all promises are ment to be broken , I don't think I'll post much more on accessnorton .
The forum is going in circles anyway .
Maybe I'll add pictures from future trips later .
Tinkering is nice .
Riding is better .
Ultimately , isn't that what it is all about ?
Ludwig" .

Regards
McVic
 
merde, that's too bad, he was a clever fellow as far as can be told from the posts I read, nothing I relish less than time consumed by re-inventing.
Anyway, I have mine, MKIII, apart and carefully measured and a solid model built.
Since this is all new to me there will be some readers who are bored, be patient please.
The more I stare the more I can see the designers intent as well as the current shortcomings.
Most likely there was a continual drain in engineering and the lesser qualified made changes at the request of bean counters.
There probably was pressure to comply with "we're out of these parts, these fit, why can't we use these?" inventory reductions, etc.
Comparing the model to the cartoons in the workshop manual is interesting. They do accurately depict the internal conditions.
The statement about hydraulic bump stop at full extension is on the page adjacent to the view with the damper valve topped out against the damper tube nut. The fellow who wrote this didn't brush elbows with one who drew it up . Sad. Extension ends when the damper valve tops out.
What I have learned is that the spring becomes solid before the main tube bottoms in the slider and is the limiting factor in compression mode.
That the damper valve tops out before full possible extension and is the limiting factor in extension mode.
The standard spring is not alone capable of slightly more than the total of the restricted motion.
Of note is the comparison of engagement length to diameter ratio of the bushings in the slider at both the standard restricted and maximum possible extensions.
At maximum possible extension the ratio is uncomfortably less than 2:1.
While staring at the model I have imagined the worst case scenario of tooling along unknown roads and encountering a series of closely spaced undulating ruts requiring application of every skill to remain upright and the resulting moment presented to the forks at full extension. With a ration less than 2:1 there will be more bending that sliding for that time interval.
All this leads me to the question, and this is where you all can offer experienced advice, why would my MKIII ever need more than the approximately 4.5" of fork travel?
 
mcvic750 said:
Tinkering is nice .
Riding is better .
Ultimately , isn't that what it is all about ?
Ludwig" .

Regards
McVic
Click to expand...

I'm with him on riding is better than tinkering. I ride mostly with modern bikes so I want to make sure that the old girl is reasonably reliable and nice to ride - hence tinkering - but only so that I can continue to look forward to the next spin.
IMHO the Lansdowne dampers are a comparatively inexpensive way to improve the suspension. And for those that still like to tinker, this kit allows you to do just that because you have to tune the damping to your personal requirements. This kit, along with Avon Roadriders, a decent front brake and a rod link head steady, extends the performance envelope of the Commando.

AntrimMan said:
All this leads me to the question, and this is where you all can offer experienced advice, why would my MKIII ever need more than the approximately 4.5" of fork travel?
Click to expand...

No need to extend the travel, but the damping needs to be improved, not least for safety. I sometimes ride with a friend on an Africa Twin. His long travel suspension is superior, but it only really shows on roads that are so bumpy that they are almost 'off-road'!

And whereabouts in Antrim do you hail from, or is it the home of your ancestors?
 
daveh said:
mcvic750 said:
Tinkering is nice .
Riding is better .
Ultimately , isn't that what it is all about ?
Ludwig" .

Regards
McVic
Click to expand...

I'm with him on riding is better than tinkering. I ride mostly with modern bikes so I want to make sure that the old girl is reasonably reliable and nice to ride - hence tinkering - but only so that I can continue to look forward to the next spin.
IMHO the Lansdowne dampers are a comparatively inexpensive way to improve the suspension. And for those that still like to tinker, this kit allows you to do just that because you have to tune the damping to your personal requirements. This kit, along with Avon Roadriders, a decent front brake and a rod link head steady, extends the performance envelope of the Commando.

Sales of lansdowne Kits are now over 240 sets , what was once a bit of a challange is now a full time job :!:

Holland Norton Works offer them as a worth while up grade,and they must be the best Commando Rebuilders.
AntrimMan said:
All this leads me to the question, and this is where you all can offer experienced advice, why would my MKIII ever need more than the approximately 4.5" of fork travel?
Click to expand...

No need to extend the travel, but the damping needs to be improved, not least for safety. I sometimes ride with a friend on an Africa Twin. His long travel suspension is superior, but it only really shows on roads that are so bumpy that they are almost 'off-road'!

And whereabouts in Antrim do you hail from, or is it the home of your ancestors?
Click to expand...
 
I and fella in Australia did measures on every component of every version of Roadholders coming to conclusion they had excess order of short springs. I solved this with valve spring spacer.

The damper rod I use is larger OD than factory about binding fit in damper cap, I sanded a waist in rod centered on the loaded sag level for progressive damping that takes all the annoyance out of THE Gravel travel.

I staggered the bottom damper tube holes so have progressive silent bottoming that can not be felt landing off 4 ft high leges.

I have played Steve McQueen up to 60 mph on lumpy pasture and hit foot deep gofer hole going 50 mph climbing a slope on fully extended forks so hard it jarred my teeth as I blasted through the exploding dirt/grass clots bounced out of saddle but bike bounced up to meet my butt on the landing so just carried on sick I'd bent forks but nothing injured at all. Forks with my 4 rate spring can not be put in a bind at full extension as they collapse instantly to any loading at all back to normal over lap range. Missplaced frear to forgetabout.

Shade tree cheap down and dirty, there may be better, don't know nor want to distract or lessen the cartridge market but my Roadholders have been solved to anything I can take. Need to have a shoot out someday, as there is a safety issue on how much forks can take before wipe outs or back offs.
 
And whereabouts in Antrim do you hail from, or is it the home of your ancestors?[/quote]
Glengormley most recently, in the US now permanently, if there is such a thing as permanence.
Ancestors, as well as the living, are in Antrim and Tyrone (around Ireland's corner), some near the Liffey too, as well as others scattered across the globe.

I was intending to just add a compliant bumper at each end of the stock travel but I think I will play around a bit with the hydraulics before I exhaust my patience.
I was hoping the Ludwig fellow was able to share some clearance vs viscosity data so I wouldn't have to go through it all myself.
The idea is to use ATF just because I have it at hand and it has desireable properties.
The stock valving with ATF is what I ended up with at the of last riding season when I changed the fork oil. It's what I used in CB450 Hondas and it worked well.
The Norton Roadholders surprised me with the topping out clanging, I thought I broke something on the first big bumpy corner encountered.
The initial oil I drained had a distinct EP smell like Hypoid but was much thinner than that while being significantly thicker than ATF.
The ATF is too thin for this application as-is even though from appearances nothing looks badly worn.
Anyone (almost) can purchase and bolt on bits and pieces. I'm more of a u-do-it type having never been able to leave well enough alone.
Thicker oil would do I suppose it worked for this long, however now that the can of worms is open I will ponder improvements.
 
OK, AntrimMan, I get your point about doing this yourself. By all means persevere. You should be able to develop something that will work, and in the process you will become an expert in hydraulics! I look forward to progress reports from time to time.

The Giants Causeway road is still good to ride and the North West 200 road race is only a month away. :)
 
I've settled on car power steering fluid as best in my modified and factory forks. But I do a lot of rough riding off tarmac and a lot of sports bike spanking so may not apply to anyone else. There have been clever mods done to the factory damper rattle valve via a spring behind or in front of it to open or close on motion to help its two way action or done opposite in each leg for single direction effect.

I'm a simpleton w/o any background to trust me on, so drilled various size and staggered holes in damper tube for progressive silent indefinite bottoming on landings, while the factory hydraulic top stops works perfect w/o any mods for silent no sense of top when fork bushes can travel far enough.
 
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