Steering Stem Bearings

[ansim]

Yes, the nut I provided is one piece nut.

As you mentioned, it is possible to make this nut 5mm lower -> the hex hight will then be 15-5=10mm.

Thoose 5mm can be used to make a new lock nut.

Or you can drill a small hole in the side of the existing nut and make 3mm threads and use a 3mm bolt as locker.

//Anders

[jcslocum]

I will try to answer your querstions as simply as I can.

It is made as 1 piece, hex on top for turning the whole nut.

After setting the proper tightening on the bearing you will use the pinch bolt to keep it from coming loose when turning the bars.

Yes you could use another nut on top as a "locknut" but that would be harder to work with. Some have recommended using a small bolt as a "set screw" but I disagree. If you have a screw come from the side and into the threaded area you can easily ruin the thread where is makes contact. This will make removing or adjusting in the future very hard to do.

The original has this split and pinch bolt so that the threads cannot be damaged. The engineer has the picture and original drawing at his desk and will be drawing it up soon. Are you in a rush to get this?? Do you have a place to have it made in Italy? I coud see about having it made here if need be.

[lceriani]

I have no hurry, because I completely disassembled the Paso and it will take a loooooong time to rebuild it... I have many parts to work on (fairingholder, center stand, tachometer, brake calipers, forks, rear shock...), so I can wait for the drawing.
I check if there is a workshop able to made it, if not I will beg again your help!

Many thanks.

[Desmo_Demon]

With the help of an eBay auction and some correspondance, it looks like these SKF 32005-X/Q steering stem bearings cross reference over to these cars, also....

I believe these are listed as...Make/Part/Year/Model/Location:

SUZUKI MX1.....5-SPEED MANUAL TRANSAXLE....1988-1985...Suzuki MX1...(RH)
NISSAN/DATSUN (FWD)....REAR WHEEL...1978-1976...F10...(Inner)
PEUGEOT.........FRONT WHEEL...1987-1977...604...(Outer)
PEUGEOT.........FRONT WHEEL...1982-1970...504...(Outer)
PEUGEOT.........FRONT WHEEL...1991-1980...505 (Exc. 2....(Outer)
RENAULT.........REAR WHEEL...1983-1978...R18, 18i Sedan...(Inner)
RENAULT.........REAR WHEEL...1983-1977...LeCar (R5)...(Inner)
RENAULT.........REAR WHEEL...1979-1982...R17, R1328...(Inner)
RENAULT.........REAR WHEEL...1977-1977...R12...(Inner)
SUZUKI (FWD).... 5-SPEED MANUAL TRANSAXLE...1988-1985...(MX1)...(RH)
TOYOTA (FWD)...REAR WHEEL....1990-1988...Tercel...(Inner)
TOYOTA (FWD)...REAR WHEEL...1987-1980...Tercel Sedan...(Inner)
VOLVO...5-SPEED MANUAL TRANSAXLE...1997-1993...(Inner)

NOTE: FWD = Front Wheel Drive


I may redo this to read Make/Model/Year/Part/Location, which would make more sense, but I'm outta here (work) until tomorrow.

[Laddie]

my advice would be ONLY to replace the whole bearing as a set - it is usually the outer race that is damaged (pitted or brinelled) in any case...

for the lock nut it really depends on if you are going for functionality or originality

you could machine up the sinlgle piece to make it look "original" but it would be just as functional using washers and standard ring nuts. you just need to put controlled thrust load on the tapered roller bearing.
the ring nuts should be available from your bearing supplier.

[dave906]

The trickiest bit of changing the steering head bearings I have found to be removing the lower inner race, which is an interference fit on the bottom of the steering stem. This was on a 906 but bearing assembly and part number is the same as 750.
I never found a bearing puller to remove it in one piece, but as I wanted to replace the bearings I removed it like this:
Take one Dremel tool or similar, add a tungsten carbide burr (~3-4mm diameter).
Cut away at one spot across the face of the race. You don't need to cut all the way through. The bearing steel is hardened and under stress by the fact that it is an interference fit. When you are part way through, the race will crack and then release its hold on the steering stem and slip off.
Try to avoid cutting anything except the bearing race, use high speed and not too much pressure - let the cutter work, and wear safety goggles & hearing protection.
To install the new lower race drop it over the stem until it won't go any further, then drive it (hammer) down all the way with a tubular drift that is just slightly bigger than the stem. The drift must only contact the top edge (non-bearing surface) of the race.

[romus]

Here is how I changed my steering head bearings after checking this site and various YouTube methods.

This thread is in the 750 forum, so I put this here because the steering head of the 750 and 906 are the same - probably too the 907ie.

The triple tree is out according to manual instructions.

I bought a 'Sealey MS040 Motorcycle Steering Stem Bearing Race Removal Tool'. It was a lot cheaper than other tools out there and was a prevention against damage when knocking out the bearing races. It hooks in behind the races and you can then knock the racers out by banging the tool with a broom handle. I could have done this with a long screw driver or tool but I used the Sealey tool again for the next stage too. So I knocked out both races.

For this job, I prepared the new and old races in the freezer to shrink the metal to make the fitting easier. I don't understand why some YouTubers also heat the stem because that expands the metal both ways - which seems to defeat the purpose.

Then, I used the old races to knock in the new races. And, as a double check for a secure fit, I pressed them as well using the large bolt that goes through the swing arm, the spacers from the swing arm and some blocks of wood. In my case I had the engine out, so I had these pieces available. A similar press could be made with big washers and a long bolt (by threading the bolt through and holding it with washers on the spare racers (that are sticking out of the stem) you can wind the bolts up to press the racers for a certain tight fit). This pressing was a double up - just knocking them in should have been enough.

Once that was done (since the old racer is stuck in just a bit in the process) I knocked the old racers out again easily with the Sealey tool.

Now that both races are nicely in the steering stem, I need to deal with the bearing on the lower part of the triple tree.

Both bearings get packed with grease.

To get the lower bearing off the lower steering tree, I cut off the inside of the bottom bearing using a cheap power tool to cut across and through most of the bearing. This released the pressure enough to get it off. Maybe it needs to be finally broken with a chisel, but I found almost cutting through it released the pressure to get it off. Actually, I got the outer part of the bearing off by a screw driver and a bit of force - I could have cut through that first.

Now to get the bottom bearing on. For this job I prepared the Bottom triple tree in the freezer to shrink the metal to make the fitting easier (making sure to get off the freezer condensation off the rod where the bearing goes).

There is a spacer on the bottom of the triple tree. I didn't even notice it until I checked the manual and was looking for the second one. Anyway, I left it on - it goes at the bottom of the tree under the bearing, duplicating the same setup on the top side.

To get the new bottom bearing on I first got the old inside bearing that I had semi-cut through and cut right through it. This made it looser and ideal as a driver to push the new bearing on. Using the smaller edge of that old cut through bearing against the inside smaller edge of the new racer it is ideal. So the new bearing and the old cut one are placed on the triple tree rod. Using this setup I knocked the cut through bearing with a chisel around the edges to force the new bearing in place to the bottom of the tree. YouTubers sometimes used PVC piping, but I found my method worked well since I already had the part and cutter.

Parts:
x2 bearing replacements
http://www.bearing-king.co.uk/bearing/3 ... q-skf/2762

x2 seal replacements
http://www.ipwparts.com/linecardpart.as ... KF%2017692