FF: Forks Modified Steering Stem

T

timetraveller

Well Known and Active Forum User
VOC Member
With the instructions which I send out with the modified steering heads I give two different designs of bracket to mount on the forks to provide the moving part of an hydraulic steering damper set up. One can be made with hand tools and the other requires access to a milling machine. I offered to get a batch made and Greg also offered to make a batch for fitting to these steering heads. Holes are already provided in the base of the steering head to allow relatively easy fitting of such a bracket. The problem is this. There is no consensus on where, or at what angle, people want the steering damper to fit. Some like it as in the photo in#90 above. Others want it to go at a similar angle down the timing side of the bike. Yet others would prefer it to go across the bike from a front drive side mounting on the forks to a fixed timing side bracket, perhaps on a crash bar. There is a sketch of such a bracket from the editor of the OzVincent Review. If anyone would like a copy of the fitting instructions so that they can look at these designs then, even if you are not going to buy a modified steering head, send me an email to enw07@btinternet.com and I will send you, by email, a pdf of the instructions.
 
greg brillus

greg brillus

Well Known and Active Forum User
VOC Member
I have had a batch made of the steering stem attachment brackets that Norman is describing in right hand configuration and a couple in left hand. Some have requested a bracket so the original friction type damper can be reused. To say this is a pain is an understatement, as the modified stem was designed to suit a hydraulic damper. It is very time consuming and expensive, so I have made two only of them to fit this kit and if anyone else asks me for it I will be telling them to sort it out themselves. The bracket that attaches the damper to the cylinder head bracket is easily made, but each is different due to everyone's personal taste, and bikes with a crash bar need room to clear the bar. These differences make it hard to accommodate every installation with one single type of damper kit.
 
macvette

macvette

Well Known and Active Forum User
Non-VOC Member
MartynG said:
Today was my first time on ANY bike since my surgery last year. I went out on my Coment with the modified steering stem, thornton shocks (coil over at rear) and the front springing described in my earlier post.

I was gobsmacked!! It was suburban riding - Hope to get it out into the countryside in the next few days. Immediate observation is that the front suspension to the eye is much more active. Under accelaration the front of the bike rises slightly; Under braking the front dips slightly - but more significant, under braking when traversing irregularities the front suspension continues to move allowing the rfont tyre to remain in contact with the road surface.

General impression is that the bike is much more planted, feels much more secure on the road. The only downside - and I'm sure I will quickly get used to it, is that the bike feels just a wisker taller than before - due I am sure to the slight but definite increase in the front end ride height.

Regarding steering damping I have fitted a Kawasaki type steering damper across the front of the motor - see photo's. I wanted to retain the crash bar and transport tie downs and it took an amount of trial and error before I got the mounting brackets working with nothing clashing anywhere.

Here are a few photo's of the damper setup - some taken without the fuel tank in place, some with it in place.

View attachment 15935 View attachment 15936 View attachment 15937 View attachment 15938 View attachment 15939 View attachment 15940

Now if you wish to duplicate my damper mounts, here are the drawings to help you do so. I made mine up from store purchased mild steel angle and strip using no more than a small angle grinder with a cut off wheel, a drill press and a bench grinder - and liberal amounts of time. The important thing is the relative position of the holes.
View attachment 15941

View attachment 15942

Hopefully more info to follow after a country run in a few days time (weather permitting)

Martyn
Click to expand...
Hi .
Looks neat, I have a couple of questions. It looks like the damper is almost fully extended on right lock in the first picture. Can you get to full right hand lock with your set up? On your sketch of the engine mount, is the horizontal portion the full 50 mm of the angle iron?
Thanks Mac
 
Martyn Goodwin

Martyn Goodwin

Well Known and Active Forum User
Non-VOC Member
macvette said:
Hi .
Looks neat, I have a couple of questions. It looks like the damper is almost fully extended on right lock in the first picture. Can you get to full right hand lock with your set up? On your sketch of the engine mount, is the horizontal portion the full 50 mm of the angle iron?
Thanks Mac
Click to expand...

G'day Mac, Look again at the drawings I posted. The measurements for the holes (which are the important bits) is done on the outside of the angle iron so yes I use almost the full 50 mm for the horisontal part - but only about 20 mm for the vertical bit. Once you have the position of the holes sorted then you can shape the outside of the brackets however you wish.

Almost all of the damper travel is used when going from full lock to full lock BUT on my Comet its the bump stops on the headstem part of the UFM thats the limit of travel, not the damper movement.

If you need to change the amount of damper travel, that may be acheived by changing the position of the damper mounting hole in the bracket that goes under the headstem - move it closer to the centre line to reduce the travel and away from the centre line to increase the travel. But take care because you will impact where the mount hole on the engine bracket needs to go. You also need to be very careful that no part of the damper makes contact with the headstem at any point of its travel.

Its a case of trial and error - I made up 4 or 5 sets of brackets, all slightly different , before I was happy with the result.

Martyn
 
greg brillus

greg brillus

Well Known and Active Forum User
VOC Member
He's nearly as fussy as me...........;)............. After Martyn and I discussed this, I have made the stem attachment brackets with the damper attachment hole further backward and inboard as well. But only because some "Strange People" like to run a crash bar............:D
 
vibrac

vibrac

Well Known and Active Forum User
VOC Member
There sits the top of the spring box and there is the bolt that holds the engine front cylinder all my racers simply put a telescopic steering damper between them simple effective and ajustable
upload_2017-4-21_9-10-2.png
 
Top