Front end diving badly

guywheatley · February 21, 2012, 09:38:23 AM

I've got a 3rd gen.. The front is diving badly to the point that taking a corner at an intersection is getting scary. I'm assuming I need to change the front fork oil. The seals are are good. I don't have oil on my forks.

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I thought about progressive springs, but decided I'd rather spend the money on something else. I'm mot going to be tearing up the Tail of the Dragon, I just need to get back to stock performance.
I found a section on Tips and Tricks about replacing the stock springs with progressives, but that didn't focus on changing the oil. I was also hoping for some photos, or better yet video, of the procedure.
What all needs to be replaced while I'm doing this. Seals? Other internal parts?
Any suggestions, or better yet photos and/or videos, will be much appreciated.

TLRam1 · February 21, 2012, 10:23:37 AM

Guy,

You can cut longer spacers to stiffen up your stock springs a little and go to a heavier weight oil, such as 15 instead of 10 wgt.

You will have to lift your front end off the ground, remove the front wheel and the fork drain screws will be up in your fork above where the axle goes through your bottom fork leg. Once you drain your fluid you will pump by hand each fork leg to remove any fluid left in the fork.

If you have a 94, maybe 95 also, the drain screws will be on the rear of the fork leg just above the axles.

lragan · February 21, 2012, 10:55:11 AM

Guy, I don't go nuts in curves either (at least not since my little unscheduled get-off about three years ago.

). In my opinion, the soft springs in the stock design are its weakest feature. Nothing I have done to the bike increased its handling to compare with installing Progressive springs.

That said, I presume you have access to the Magna repair manual? It tells the procedure pretty well. The only caveat is in measuring the oil level. The manuals don't make it clear, but they refer to the amount of air between the oil level and the top of the strut -- not the level of oil measured from the bottom, through the spring. Hence a lower number is more oil, not less. In measuring this distance, one has to decide where to place the tape, ruler, whatever, as the tubes are not vertical if on the bike. So if you measure at the front of the tube, you get one number, at the back a smaller one.

What I have done is use a ruler that is almost the diameter of the tube, and insert it so that the surface of the ruler is parallel to the front axle (if it was on the bike, which it won't be for this procedure), in other words, across the fork, parallel to the long direction of the front of the triple tree. This gives me a reading that is the average of the front and back. I am sure there are other ways to do this, and I am not certain how much difference it would make in the final result, but it works for me.

It seems highly unlikely to me that your springs have fatigued or sagged, but I suppose it is possible. If the oil seems OK (not dark colored or full of sediment) and the seals are smooth and not cracked, and the spacers have not collapsed, then tired springs seems the only other theory I can offer. If you are still set on staying stock, and need replacement stock springs, I believe I still have a pair that are yours for the shipping cost.

guywheatley · February 21, 2012, 11:10:37 AM

Thanks for the input guys. Terry, I do have a 94, and the oil drain is right where you said it would be.

I also remember Charles using longer spacers in his. I think I'll replace the oil with 15 wt and bump the spacers up about 1/4 inch.
We'll see what that does.
Again guys, thanks for the advice.

Ingramml · February 21, 2012, 03:36:36 PM

I am having the same problem after changing my fork oil and seals. Was leaking out of the bottom tightened bolts to stop leak. What are you guys using to measure your fork oil. I plan to drain oil and remeasure again this weekend. I want to be exact this time.

silveradocowboy · February 21, 2012, 04:27:36 PM

Ingramml...

I use a container that has metric measurements, just need something similar or convert it to US measurements. The 1st gens use a certain amount of fluid in each fork, the difference is that one fork has the TRAC sytem. Progressive springs and going to 15 wt. oil also helped my '85 V65. Also you might check the air pressure in the forks, think it is 0 - 6 psi, a hand pump works great for this so you don't blow out the seals.

lragan · February 21, 2012, 04:45:40 PM

Quote from: silveradocowboy on February 21, 2012, 04:27:36 PM
Also you might check the air pressure in the forks, think it is 0 - 6 psi, a hand pump works great for this so you don't blow out the seals.

Jeff, now you have me confused. On my '96, I don't see a way to inject air into the assembly. Don't see anything in the manual about adding air. Of course, I assemble the whole thing with no weight on the bike, so when it compresses, there will be air pressure in the tube. I suppose I could measure the compression and calculate the pressure, but why?

Is this air injection unique to 1st gen bikes?

TLRam1 · February 21, 2012, 05:11:13 PM

Lawrence,

The added air pressure does not pertain to the 3rd Gen bikes.

Ingramml · February 21, 2012, 08:10:05 PM

I got snowed into some Honda suspension oil that is red. I got it form the local Honda store. I let out all the air and it still rides unbalanced. I have wondered if putting my tire on different from the way I originally had it on would effect it.

Jerry G Turner · February 21, 2012, 08:28:46 PM

How can you put the tire on differently.

Lurkin · February 22, 2012, 09:18:03 AM

Just a couple of notes here. When I was researching fork oil a few years ago I found out that the fork oil weights are not standardized as they are for motor/gear oil. Different manufacturers could conceivably label a fork oil that has the same viscosity range as a 10w for one and a 15W for another. At the time I found a table that listed the viscosity ranges for different fork oils that I used to ensure I got what I wanted. Not sure if this is still true or not, but might want to research.

Also, for fork oil level what I found that worked well was a syringe-like thing that was made for measuring 2-cycle oil. I filled the fork tubes a bit over, I measured the syringe for the proper oil level, marked the syringe, then inserted the syringe into the middle of the fork and just pulled out the fork oil until it was pulling air. This worked better for me then any of the create-a-dipstick methods.

BTW, I found the syringe at Walmart.

Ingramml · February 22, 2012, 10:14:57 AM

I have looked and I have gotten different amounts of oil for my magna. I have been told by the same honda store 18.4 and 18.9 ounces right and left respectively as well as 12 and 12.5. Does anyone know for sure or have the official manual (clyme has 18.9 and 18.4 ) for the 86 v45 to tell me exactly how much oil goes in each fork. I am going go call again today but I don't have a lot of faith in them.

Greg Cothern · February 22, 2012, 04:15:00 PM

If I were to get into it, I would put in Progressive units, hands down!!! Remember springs of any brand do sag etc over the years.

One of the top 3 must have upgrades for a 3rd gen Magna!!!!!

Jigger · February 22, 2012, 07:15:59 PM

My bike had the same problem as yours. Mine would dip when ever I used the front brake no matter how lightly I would use them. If I came to a stop sign or light. It seemed like my forks were going to bottom out. So I changed out the springs and replaced them with Progressive. The change was like night and day. Springs over time will loss thier tension stength. So I would imagine your springs have become soft.

TLRam1 · February 22, 2012, 08:40:03 PM

Quote from: guywheatley on February 21, 2012, 11:10:37 AM
Thanks for the input guys. Terry, I do have a 94, and the oil drain is right where you said it would be.

I also remember Charles using longer spacers in his. I think I'll replace the oil with 15 wt and bump the spacers up about 1/4 inch.
We'll see what that does.
Again guys, thanks for the advice.

Good deal Guy, when I bought my 01 Magna I switch my 94 forks over partly because of the easy access to the fork drain bolts.