Author Topic: Created jack-up device to raise the front end (suspension work on front tubes)  (Read 2622 times)

JeffK

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I used to take an hydraulic jack under the exhaust manifold or engine to raise the front end on ICE bikes.
On the Empulse the "belly" contains vulnerable electronics which will be squished if the traditional method is to be used :o

Today I will be creating paddock stand that raises the front end, using the crash bung mounting points.
I started by adding spools to the crash bungs that I mounted last year.



The spools are from Rothewald, opened up to 10mm. to accept the crash bung bolt.

Now it is time to scavenge some iron bars.. back in a few hours
« Last Edit: September 24, 2015, 08:44:50 AM by JeffK »
Modifications so far:
Crash bungs
shortened chain tensioner bolts

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JeffK

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the object is to create a bike-lift that catches on both spools.
I am going to convert this Telefix Cruiser lift:

Modifications so far:
Crash bungs
shortened chain tensioner bolts

Top Case

JeffK

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So, as work continued I changed plans a bit.
I was a bit short on time, so I skipped welding the hooks on top of the bars that would catch the spools.

Work on steering head bearings and suspension would not be performed often, so I decided to just drill holes in the bars and fix them to the frame with the crash bung bolts.

Works pretty good and only a little more work to fasten the bolts.





Next job: sort the front suspension, figure out the air chamber, oil grade etc.

[edit]No, next job is to tighten the steering head bearings, discovered they have excessive play[/edit]


« Last Edit: September 24, 2015, 10:13:03 AM by JeffK »
Modifications so far:
Crash bungs
shortened chain tensioner bolts

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JeffK

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Not happy yet with the bolt-on solution, so I went looking around the shed for a decent "fork-style" ad-on for the jack arms.

There you go, a 18-19 mm spanner.



and welded to the jack arms.


So, how does it function.... check vid:




« Last Edit: October 09, 2015, 02:06:43 PM by JeffK »
Modifications so far:
Crash bungs
shortened chain tensioner bolts

Top Case

Shinysideup

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Sweet! Love the wrenches.

vtbrammorider

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So, as work continued I changed plans a bit.
I was a bit short on time, so I skipped welding the hooks on top of the bars that would catch the spools.

Work on steering head bearings and suspension would not be performed often, so I decided to just drill holes in the bars and fix them to the frame with the crash bung bolts.

Works pretty good and only a little more work to fasten the bolts.





Next job: sort the front suspension, figure out the air chamber, oil grade etc.

[edit]No, next job is to tighten the steering head bearings, discovered they have excessive play[/edit]

Check the 6000 mi post in HOW TO.  I put the fork info in there.
http://brammoforum.com/index.php?topic=3044.0

JeffK

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Check the 6000 mi post in HOW TO.  I put the fork info in there.
http://brammoforum.com/index.php?topic=3044.0
Aaah too late vtbrammorider, I just put them back together this afternoon.

Here's what I came up with:
There was only 300 cc in each leg.
Viscosity was and estimated 7.5W so that is in par.
Air chamber: 15 cm, as to be expected with only 300 ml. of oil.
There is a 25 cm linear spring with an estimated spring rate of 9kg/cm.

This seems to be a pretty stiff, considering bike and rider weight, intended use (commuting, public roads) and will take it's toll on steering head bearings and rider comfort.
Also I have noticed that I am only using the upper third portion of suspension travel on the tubes, despite the pre-load at its lowest setting.

I will try and find a 7 kg/cm spring.

I put the legs back together using 5W oil, seems to soften things up a bit, but not enough to my likings.
Modifications so far:
Crash bungs
shortened chain tensioner bolts

Top Case

vtbrammorider

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Interesting,  I'm seeing almost full travel (but I am tracking it).  The eurosports guys are who confirmed my spec on the forks.