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Discussion Starter #1 (Edited)
I replaced the fork seals tonight, nothing unusual other than the seals just sliding out on their own when I pulled the tube out. I was replacing them anyway, so big deal.

I grabbed some Castrol Transmax Import Multi-Vehicle ATF from Autozone (It doesn't show what weight it is, the datasheet doesn't seem to help either) - looking at the wrong part of the manual, I added 4.6 ounces, which is indicated for the CB. Found the CM section and saw I'm short about 2 oz.

Anyway, I got everything back together, torqued everything down, put 10psi in and now it's squishy as ****. Took it for a short ride and it's sketchy as hell. I didn't touch the tree, other than getting the forks out and back in, but it feels real strange - almost as if it'd start to tank slap if I let go of the bars. It also seems to pull to either side when going into a turn. Left turn, the bars pull left, etc. I'm used to them being pretty neutral and not pulling either way.

So - I assumed 2 ounces short would make things a bit stiffer. Will adding 2 more ounces help? Anyone know what weight this crap is? I probably should have paid more attention when I was buying it. it seems pretty thin. I'm guessing it's 5w. Anything else obvious I need to check for?

With the front wheel off the ground, I'm at 6.5" from the top of the dust cover to the bottom tree. When I'm sitting on it, it's just about at 4".
 

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that front end is one of my least favorite. it's not got a lot of rigidity and is very succeptible to misalignment loosen all your gear , especially the fender, put the bike on a pit bill stand and make sure it's pin straight. snug the fender first, then the lower tree clamp , then the top. if your tires are old you'll feel that pretty badly too. those 2oz will help slow the dive , but the wobble is definitely alignment and or tire
 

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ATF is about 10 weight...it's much better to use real fork oil..

I recommend going up just a tad to 12 or 15 (I typically but 10 weight and 20 weight of the same brand then blend them to achieve the correct combined weight)

you also have too much static sag. to set sag, get on the bike in your riding gear. have a friend hold the bike while you sit on it. have a 3rd friend measure the sag.

your target is 20% of total travel...about 1 inch assuming total travel is 5 inches.

to stiffen you need to make and add spacers to the spring. I use PVC pipe for spacers. you're spacer will need to be about 1.25" (slightly less then the delta you are trying to take up)...install them and retest sag...adjust spacers as needed to achieve 20%
 

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Discussion Starter #4
Thanks guys. I'll give realignment a shot. I don't have a pit bill stand.. maybe a trip to Harbor Freight is in order. Last night I used car stands on either side of the highway bars.

So, the fender... I'm not sure it's straight to begin with. What are you thoughts on putting it on last? Put wheel on, tighten the lower, upper and then putting the fender on. If it's not straight to begin with, seems like it's starting me off poorly to begin with. I defiantly need a new tire.

I've give all this a shot as post back. @phil71, let me know what you think about the fender thing.
 

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your car stands are okay for that purpose . I like to lift it at the stem if I can, but no biggie. I don't understand what you mean about putting the fender on last. put it all together with everything snug but not tight. align , torque. I would still say fender first ..
if your tire is bad enough, nothing you do is going to make the bike feel safe
 

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Discussion Starter #6
your car stands are okay for that purpose . I like to lift it at the stem if I can, but no biggie. I don't understand what you mean about putting the fender on last. put it all together with everything snug but not tight. align , torque. I would still say fender first ..
if your tire is bad enough, nothing you do is going to make the bike feel safe
My thought is that if the fender isn't straight (I think it's bent a bit, the fender never looked straight to begin with), I'm starting crooked to begin with... I'll try again with the car stands again.

The tire needs replacing, but isn't that bad. It's def on the list.
 

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like the cb360, the 400 series forks are a little flimsier than the cb350 twins . I've noticed the fender-as-brace is integral to the suspension .. it sounds like you're hoping to rely on it less because it's not in good shape .. but it's part of the design, it doesn't really work without one of its parts.
 

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for further clarification, the forks don't care if the fender is straight...what they do care about and the reason you put it on first is so that it's not under tension...meaning that the holes for the bolts line up without you having to push or pull on them to attach. after the front end is fully assembled in the correct sequence it's fine to bend your fender back into shape at that time...after everything is properly installed and torqued.
 

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Discussion Starter #9
for further clarification, the forks don't care if the fender is straight...what they do care about and the reason you put it on first is so that it's not under tension...meaning that the holes for the bolts line up without you having to push or pull on them to attach. after the front end is fully assembled in the correct sequence it's fine to bend your fender back into shape at that time...after everything is properly installed and torqued.
Gotcha. That's what I wanted to know. So the correct order of thing is tighten Fender, lower, upper - torque fender, lower then upper, install wheel?
Turns out this 1" bit of pvc makes getting the caps on a real pain in the junk.
 

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Discussion Starter #10
Alright - 2oz fluid added, so I'm at manual spec. Installed 1" spacers. Everything's back together.

Notable issues:
When the brake caliper is tightened to spec, the wheel doesn't rotate freely. Perhaps bleeding them will fix it, or just riding it? It's definitely the pads.

It rides A LOT better now, but there's still some minor pull - it's much better tho, so I'll call it progress. I think I'll tighten the head up a bit. I didn't losen it, but perhaps the forks coming out did it?

Something still isn't right with alignment (This isn't new), but I can't see why at all. It's as if something's bent (forks are good). When riding the bars look and feel like their turned slightly to the right. Maybe one of the top bridge bits that holds the bars is bent? This is something I've tried to correct since I got it. Seems obvious to try loosening the top, twist a bit, then tighten - but nothing. Meh.

IMG_20140808_144720359_HDR.jpg IMG_20140808_144726073.jpg
 

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Could you post a pic of the front wheel straight on? In the last pic , it looks like something is still off, and your brake rotor dragging is another issue that has to be looked at.
Maybe it's all related.
 

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On the oil level. I have found doing the six inches down method works very well.To do the six inches down method. Remove the caps, remove the springs. Fully compress forks. Now pour in about 50% more oil than recommended. I use a Miti Vac tool. On the end of the hose put a zip tie on the hose, six inches from the end. Put this end down into the fork so the zip tie is at the top of the fork. Now draw off oil. Any above six inches gets drawn out, Any below six inches stays. I use just plain old tranny fluid. Been used by people for many years and works well. Experiment with different oil weights if you want. Leo
 

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ATF contains detergents and other additives. It has been used for many years... Actual fork oil is vastly better
it has consistent viscosity and doesn't attract moisture and is much better at reducing wear

one clarification on the tightening sequence... Just like the fender, the objective it to have none of the components under tension when torqued with the lower sliders perfectly parallel to prevent stiction in the movement of the fork slider
Fender
wheel
lower triple
steering stem nut
top triple pinch bolts


doing the top triple and stem may require a few tries to get perfect
you want as little tension as possible on the steering stem bearings
just enough so that there is no play
tightening the stem bolt adds pressure the the bearings so I leave the bearings just a tad too loose so that tightening the stem nut makes the last bit of play out of the stem bearings

if your stem bearings haven't been cleaned and regreased recently then now is a good time to do it

lastly, if there is any play in you fork sliders, wheel bearings or steering stem your front end will transmit that to you as squishy ness and wobble. After that is sorted next true your wheel and mount and balance a new tire
 

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Discussion Starter #14
Could you post a pic of the front wheel straight on? In the last pic , it looks like something is still off, and your brake rotor dragging is another issue that has to be looked at.
Maybe it's all related.
Here's head on, and either side. You can see the left (right in photo) bar is up higher. This evening I'm going to try alignment with the dive method - loosen everything below the top tree, drive the forks down a bunch and ideally, it'll align itself.

IMG_20140809_151511.jpg IMG_20140809_151549.jpg IMG_20140809_151601.jpg
 

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Discussion Starter #15
Worth noting that the left (pictured right) higjwaybbar is bent back some, and off another bike.
 

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Yeah those bars are screwed up. Good noting it is bent.
 

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like the cb360, the 400 series forks are a little flimsier than the cb350 twins . I've noticed the fender-as-brace is integral to the suspension .. it sounds like you're hoping to rely on it less because it's not in good shape .. but it's part of the design, it doesn't really work without one of its parts.
Would an aftermarket fork brace be in order for bent or missing fenders or even just as an addition to the front end for greater stability?
 

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Discussion Starter #18
Alright, I loosened everything below the top tree, and dove the **** out of it. That helped a lot, it didn't feel like death and I was able to let go of the bars with no immediate wobble. I braked real hard a few times to make sure the forks were solid too. I might be crazy here, but I feel like doing so put it back off slightly.

It still felt a tad bit off, so I did it again, this time giving it a good twist with my legs holding the wheel. I think I"m at about 98-99% now.

I've got a new tire on the way. I think when I take it to get put on, I'll have the shop have a go at it too.
 

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I'm having really similar problems with my '78 CB400. Just did a quick fork seal swap and threw some new tubes and tires on. When I put it all back together I have a ton of dive in the forks and my front tire is misaligned exactly the same as yours. When I first rode it down my street after assembly, I thought I was going to flip over my bars when I turned, even if at a really slow speed. I'll see if I can fix the dive with higher weight fork oil (I used 10w and I'm a fairly small guy) but the alignment is driving me nuts. I've taken the forks off, put them back on, checked everything over and I can't figure it out. The forks are straight but when I get them back in the tree, the rider's right fork seems to be ever-so-slightly off. That, in turn, sends the front tire off to the left a bit.
 

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When you say the forks are straight do you mean that you actually checked the fork tube straightness with a straight edge while they were apart?
10w fork oil should be sufficient, maybe 15w but I wouldn't go higher than that. Have you checked preload and sag yet?
 
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