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Installing fork boots and fork oil level

Started by Old Rider, May 14, 2021, 07:08:11 AM

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Old Rider

Since the rain has been pouring down for days and the fork boots i installed last year was made of bad quality rubber that has cracked allot i put the bike in garage to replace the boots
like to protect the fork seals from dirt and water and the innertube from stone chips that can be expensive.I have repaired small stonechips on innertubes before by replacing seals  sanding and polishing the metal on the 1100 i had before but don't want to go that route again.
In the same time i raised the fork oil level from 141 to 130mm .I also measured the fork oil level with the springs installed for a easier check later.
since it rains still i made a little writeup

Old Rider

Since not all pictures came in  the first post it continues her  :pardon:

Old Rider

I got a little tired of the yellow forkboots so decided to go back to black.The black i made this time is similar to the yellow named pro-grip
The material in these boots seems very god quality no signs of cracking like the first black boots i made from steearing rack gaiters.
Only thing is the material is not ordinary rubber so to make the gorilla glue bite you have to use sandpaper to rub up the surface first.
The yellow that i tok off is still in great shape and the glued seam is still strong.

Pat Conlon

Yes, those black boots look so much better than the yellow....nice job.

My Honda CB's I had in the '70s had fork boots so I never worried about rock nicks on my stanchion tubes developing into fork seal leaks. I've often wondered why the manufacturers stopped using them? Style?
It was step backwards in my opinion.

Now, if there only was a way you could incorporate a fork brace in with those boots.  
Those skinny 41mm dia. stanchion tubes on a 550lb bike carrying 250 lbs of rider and gear....needs a fork brace!
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Old Rider

Quote from: Pat Conlon on June 12, 2022, 09:06:49 AM
Yes, those black boots look so much better than the yellow....nice job.

My Honda CB's I had in the '70s had fork boots so I never worried about rock nicks on my stanchion tubes developing into fork seal leaks. I've often wondered why the manufacturers stopped using them? Style?
It was step backwards in my opinion.

Now, if there only was a way you could incorporate a fork brace in with those boots.  
Those skinny 41mm dia. stanchion tubes on a 550lb bike carrying 250 lbs of rider and gear....needs a fork brace!
Thanks I got a little sick of the yellow

I dont know why they stopped using them maybe style or maybe more money in riders have to buy new/or repair tubes and
the service cost that comes with that.I had rocknics before that i could repair ,but sometimes the innertube has to
be replaced.

Yes i agree and know about the forkbrace problem it is always something in the way  :smile:.I think maybe you can have both, but then the forkboot must be cut shorter and will be lose in the lower point
I have not found it to bee crucial with a forkbrace on the fj then you have to ride very hard, but when i some years ago  installed a pair of forks i had ovehauled i made a movie with a little camera placed on the sidescoop.
I made the movie to see how the how the suspension setup was.I placed a strip on the innertube right over the
dust seal to se the suspension travel and sag.When i watched the movie later i could see that it seems to be some
twisting in the forks when braking .i did not notice when i did the ride.Last year i had a little hgspeed wobble
on a trip that caught me by surprice, but the reason was easy to find because when checking front tirepessure afterward it was only 19 psi so i had got a little puncture.
I will se if i can find the movie and post on youtube .Im not 100% sure it is the forks twisting but it looks so

Old Rider

I uploaded the video i tried to edit it cutting away the parts that was not needed but my editing software did not vant to cooperate https://www.youtube.com/watch?v=3fHh3QOU0Ps

Pat Conlon

The best solution I have seen (so far) came from AVFred....he found a bug/rock shield that fit inside the fork slider as part of the dust shield. That way the fork brace could still be used because it clamped to the outside of the slider.

I see RPM sells those shields. http://rpmracingca.com/proddetail.asp?prod=ForkSeal%26Protector

Not as good as a full circumference boot but better than nothing.

Perhaps if we had a more modern front end (like the Bandit, XJR or FJR which uses 43mm fork tubes and 17mm axles)  I could be persuaded that a fork brace would not be needed, however, with our oem 41mm tubes and 15mm axle and the laden weight of our FJ's, I firmly believe that a fork brace is highly beneficial.

Ever wonder what's cracking our fender tabs?
It's deflection.
Take the aluminum strap off the top of the front fender. See the 4 holes in the strap for the 8mm bolts? Look at the holes. Are they round? They were round at one time. What caused the holes to get elongated?
It's Deflection.
I find noticeable the fork brace benefits on quick left right left right transitions.

Cheers
1) Free Owners Manual download: https://tinyurl.com/fmsz7hk9
2) Don't store your FJ with E10 fuel https://tinyurl.com/3cjrfct5
3) Replace your old stock rubber brake lines.
4) Important items for the '84-87 FJ's:
Safety wire: https://tinyurl.com/99zp8ufh
Fuel line: https://tinyurl.com/bdff9bf3

Old Rider

Quote from: Pat Conlon on June 12, 2022, 03:15:05 PM
The best solution I have seen (so far) came from AVFred....he found a bug/rock shield that fit inside the fork slider as part of the dust shield. That way the fork brace could still be used because it clamped to the outside of the slider.

I see RPM sells those shields. http://rpmracingca.com/proddetail.asp?prod=ForkSeal%26Protector

Not as good as a full circumference boot but better than nothing.

Perhaps if we had a more modern front end (like the Bandit, XJR or FJR which uses 43mm fork tubes and 17mm axles)  I could be persuaded that a fork brace would not be needed, however, with our oem 41mm tubes and 15mm axle and the laden weight of our FJ's, I firmly believe that a fork brace is highly beneficial.

Ever wonder what's cracking our fender tabs?
It's deflection.
Take the aluminum strap off the top of the front fender. See the 4 holes in the strap for the 8mm bolts? Look at the holes. Are they round? They were round at one time. What caused the holes to get elongated?
It's Deflection.
I find noticeable the fork brace benefits on quick left right left right transitions.

Cheers

You have some good pointe there Pat. When you mention it i remeber that the holes in the aluminium strap was a little oval.The design of the that piece and how it is fitted is not good.
Maybe if it was made of thicker material and fitted under the fender so it is bolted directly to the tabs on the forks vould have made things stiffer.