FJowners.com

General Category => Maintenance => Topic started by: azure on May 15, 2017, 10:30:23 AM

Title: Belated Spring greetings!
Post by: azure on May 15, 2017, 10:30:23 AM
Man, it has been hard to get into an FJ, or any other m/c frame of mind this year. New England weather is still grimey, 40s and raining for days. I finally decided to get out of town,  planning on heading out ASAP to view Barber's new building addition and the complete collection via the Blue Ridge Parkway, arguably my favorite road in the U.S., at least so far! Started prepping the FJ as a possible conveyance. So nice to get into bike mode! I prepped my carbs, all spiffy, with new diaphragms and slides, jets cleaned etc, now going to put in Racetech springs and RPM fork valves with block off plates, feels good, and hopefully the weather will smile a bit and become more hospitable for my departure!


Here In MA, all bikes have to be inspected and stickered by May 31, which has been a meteorological challenge to date. I've got 2 done so far, but am anticipating lines and waiting for the remainder. Might be a really good reason for taking a day off work, no? :biggrin:
Happy riding to y'all, Ben
Title: Re: Belated Spring greetings!
Post by: Sparky84 on May 16, 2017, 08:00:25 AM
Quote from: azure on May 15, 2017, 10:30:23 AM
now going to put in Racetech springs and RPM fork valves with block off plates,

Do you need to fit block off plates to anti dive when installing RPM fork valves?

Cheers Alan
Title: Re: Belated Spring greetings!
Post by: FJmonkey on May 16, 2017, 08:09:45 AM
No, with the RPM valves you can leave the AD on or take them off. For inexpensive block off plates I have seen the AD unit split and the lower half inverted and put back on.
Title: Re: Belated Spring greetings!
Post by: aviationfred on May 16, 2017, 08:12:23 AM
Quote from: Sparky84 on May 16, 2017, 08:00:25 AM
Quote from: azure on May 15, 2017, 10:30:23 AM
now going to put in Racetech springs and RPM fork valves with block off plates,

Do you need to fit block off plates to anti dive when installing RPM fork valves?

Cheers Alan


No, the anti-dive units can be left as is. A few members have install block off plates since the anti-dive units can leak and most function poorly if not at all.


Fred
Title: Re: Belated Spring greetings!
Post by: Sparky84 on May 16, 2017, 08:32:41 AM
Quote from: FJmonkey on May 16, 2017, 08:09:45 AM
No, with the RPM valves you can leave the AD on or take them off. For inexpensive block off plates I have seen the AD unit split and the lower half inverted and put back on.

Will the anti dive still function with the fork valves?

Quote from: aviationfred on May 16, 2017, 08:12:23 AM
No, the anti-dive units can be left as is. A few members have install block off plates since the anti-dive units can leak and most function poorly if not at all.


Fred

I do notice that anti dive does still function when applying brakes, (less travel in forks under compression while braking) whether they are working how they should, that I cannot tell due to it has always been this way.

Cheers Alan
Title: Re: Belated Spring greetings!
Post by: azure on May 16, 2017, 10:44:22 AM
My anti dive units were malfunctioning, so I have installed block off plates, sourced from a Canadian Ebay vendor, as I recall
Title: Re: Belated Spring greetings!
Post by: great white on May 16, 2017, 11:19:41 AM
Quote from: Sparky84 on May 16, 2017, 08:32:41 AM
Quote from: FJmonkey on May 16, 2017, 08:09:45 AM
No, with the RPM valves you can leave the AD on or take them off. For inexpensive block off plates I have seen the AD unit split and the lower half inverted and put back on.

Will the anti dive still function with the fork valves?

Quote from: aviationfred on May 16, 2017, 08:12:23 AM
No, the anti-dive units can be left as is. A few members have install block off plates since the anti-dive units can leak and most function poorly if not at all.


Fred

I do notice that anti dive does still function when applying brakes, (less travel in forks under compression while braking) whether they are working how they should, that I cannot tell due to it has always been this way.

Cheers Alan

I can't speak for the FJ specifically since mine is an 89 (no anti-dive units) or the RPM ones since I haven't worked with them, but I did put RT emulators in my 83 Venture:

(http://i1174.photobucket.com/albums/r618/justonepict/B52078EB-FE8A-4832-9672-1D97CCA9021E_zpsxijzaafc.jpg)

It has 86 forks (first year that will fit R6 calipers), but it's the same idea except the anti-dive is activated electrically (brake light circuit) instead of hydraulically.

What happens with the emulators (IE: fork valves) is it basically "inerts" the anti dive. It does this because you have to enlarge the damper holes in the tubes in order to flow enough fluid to have the valves work effectively. In the process of adding/enlarging the holes, you basically route fluid around the anti dive units, making them ineffective. Well, more ineffective I guess.....  :wacko1:

If you had to alter the earlier FJ damper rod forks in a similar way, I'd say it's likely your anti-dives are none functional.

Where most people end up thinking that the anti dives are still working is that the low speed valving is much better with emulators/fork valves. Have a read of race tech's installation instructions, paying particular attention to item 6: http://www.racetech.com/download/IP_FEGV_FIT_web.pdf (http://www.racetech.com/download/IP_FEGV_FIT_web.pdf)

:dance2:

Most other 80's brands owners that use hydraulically activated anti-dives disconnect them after installing emulators, citing everything from improved braking action to elimination of extra air trapping or leak points. I would think the early FJ's would benefit similarly.

:gamer:

Title: Re: Belated Spring greetings!
Post by: great white on May 16, 2017, 12:11:27 PM
Hmm, read up on the RPM valves. Seems they are different in that they don't seem to require drilling the damper rods.

My previous post may to apply to the RPM valves....