Author Topic: James' 77 550f.  (Read 48994 times)

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Offline luceja

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Re: James' 77 550f - resto-mod, now with mags!
« Reply #75 on: May 27, 2011, 12:34:02 AM »
Nice score on the loot. 8) What is your method of assembling the lower cases?

I'm making this up and I'm sure someone can provide better guidance...

(77 550f) Assuming case is bare but all parts (gears, crank) are assembled:
- clean again. I like compressed air.

Bottom half:
- if the bearing by the oil pump is out, heat up case in oven for a little bit and it should pop right in.
- put in oil guides, etc. Mine has two, one under crank and a black plastic one.
- press in oil seal for the shift shaft/arm thing.
- pop in crank bearings
- put oil seals on crank
- optional - put hondabond on crank oil seals. no idea if this is kosher. my method is to just hondabond half of the seals as I put them into the bottom of the case. When I join the cases later, I hondabond right onto the case including along where the top half of the seal is. Either way, the seal gets a little hondabond.
- lower crank w/chains and oil seals on it onto the bearings. I use lots of lube on the bearings and because I'm paranoid.
- put starter clutch onto primary chain.
- slide the shaft that goes through the starter clutch in. be careful with the roller bearings on the shaft and jiggle it together. With my case, I always have to lightly tap it in (or out) with a few gentle taps from a hammer right at the end. The bearing should be flush with the case.
- This is a good time to confirm that your primary chain isn't touching the bottom of your case, assuming you are using an old chain.
- do the kickstarter. I always refer to my manual to get the spring/washer order. I basically put something on the table in front of the shaft to hold it in against the spring while I fit the inner parts and put on the clip. Basically the sprocket near the case should spin freely unless you turn the shaft. I think the one thing to figure out is how the outer return spring on the outside of the case goes.
- drop the two gear shafts in. Note how the holes line up with the cases so the pins/oil passages line up.
- put in the two oil seals on the left side of the gear shafts. Again, I chose to lightly hondabond the oil seals to the case.
- I prefer to put the gears and shift forks in neutral for when I join the cases.

top half:
- put in the alignment dowels
- pop in crank bearings
- I think the drum shaft has an oil seal on the small end, I forget there. Maybe not.
- slide in shift drum, putting in the big fork as you do. Note how the fork goes- basically the side with the pin will be to the rider's left when it's all assembled?
- Drop the pin in the big fork and I use pliers to push the clip in that retains the pin.
- slide in the rear shift fork shaft, putting on the forks as you go. if you're unsure of which forks goes on the left and the right,  put them spin the shift drum while holding the forks up to note how the motion should go. If you have it wrong you won't be able to spin the drum properly.
- put in the starter gear. you can see in my photo above how it goes - the teeth of the small gear line up with the shaft in the bottom of the case when you look at it.

joining:
- wipe off case mating surfaces (I use acetone)
- assembly lube the crank bearings, etc again
- very light hondabond all around. I prefer to do the top case, not the bottom, just for visibility.
- I do not know if you are supposed to HB the towers that hold the crank in, assuming there might be an issue there with crank bearing specs. I split the difference and did an extremely thin coat on those towers.
- I generally barely HB near the clutch side, since oil leaks are a non issue there. I do put HB where the crank and tranny oil seals will sit.
- start to drop the cases together. I position the rods vertical but they often fall. A helper would be nice there.
- at this point the shift forks are probably stopping the back of the case. look in there and you'll probably have to push the inner big fork into it's slot.
- it should drop together more.
- Make sure the two tranny bearings are aligned. There is a metal half circle clip thing on each that that fits into a groove on the upper case and on the bearing. if it's not lined up, tap it left and right until the cases drop together more.
- If things still aren't flush, it may be that the little pins at the end of the tranny shafts aren't lined up with the holes in the cases. again, jiggle things.
- Things should be flush now. I start threading in the case bolts on the top just finger tight and then tilt the case and do the ones on the bottom. If I recall the manual has you do the crank bolts first, then all the little bottom bolts, then the top. I'd refer to the manual for the crank bolt order and all the torque specs - I got it off of this site and can relay that part if needed.



'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline Flying J

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Re: James' 77 550f - resto-mod, now with mags!
« Reply #76 on: May 27, 2011, 03:24:10 PM »
Thanks for that.Lots of good info.

Offline luceja

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Re: James' 77 550f - resto-mod, now with mags!
« Reply #77 on: September 03, 2011, 10:14:00 PM »
Like projects do, the 550 has grown a ton. It could have been just fixing the motor and riding it.

The momentum got stuck on the motor for a few months. Cases, cylinders, valve cover, oil pan, and clutch cover were all painted months ago, but the head and it had oxidation all over it. It needed to be dissembled and cleaned pretty rigorously before painting, and much of the casting lines were filed and ground off for no good reason. Finally this got done today. Only a few more steps to try to see if it'll run.



The shelby dowd wheels are 750 fitment, with a wider sprocket offset than a 550, but as it turns out someone already machined the exact amount needed off of the sprocket side of the rear wheel... meant to be, huh? The wheels were pretty rotten with oxidation and had some rough casting flashes, and it was pretty time intensive cleaning all the cast and machined surfaces, masking and hand painting. Only the front is done so far.



To me these wheels completely define the bike. I had a fair amount of internal debate about taking the spoke wheels and rear drum off, but the bike really has it's own momentum now and feels like it's making it's own choices. A friend of mine had a great quote - "do what's right for the bike". In this case, the wheels are the most unique part and sort of set the theme. They are heavier and actually thinner than the stock spokers, the front dual disc and rear disc are totally unnecessary, there's no cush drive, so the theme isn't really high performance. I don't know how I'd describe it, but it all sort of adds up to me.



One oddity was that the front wheel's disc mounting holes were all spot-on on the left, but clearly askew on the right, as if the folks over at shelby dowd didn't have a very good drill press or never intended dual disks. Either way, the holes on one of the discs had to be filed to fit the hole pattern problems on the wheel. The 750 caliper brackets that came with the wheels were bent inward and seem to work on the 550.

The rear wheel is disc and needs a master cylinder, so I've sketched up a bracket to connect a 5/8 master cylinder off a 600rr to the stock brake level spindle. 5/8 seems large, so hopefully the bracket geometry will help with that. The rear wheel will need axle spacers, a caliper bracket and a brake stay. Both wheels will need bearings. Luckily cyclexchange has 37t cb750 sprockets, which will allow stock 550f gearing on this bike.

The muffler is a harley fitment supertrapp megaphone. Turns out it's the exact same pipe size as the 550 at the collector so it just needs a simple gasket/clamp, and it turns up nicely without blocking the rear axle. It will be cut a little shorter than in the mock up in the photo. It's been really hard to find anything except for the mac muffler meant for the stock 550f headers.





The rear fender is rotated inwards and lowered with aluminum brackets. It may need a more solid brace if the back is flexing without the stock arch. It may also rub like hell. The inside was a bit rusty so it was thoroughly cleaned, masked, and painted black inside.





The gauges being used are held on with a simple aluminum bracket that makes room for the ignition cylinder. Currently there's no ignition switch or idiot lights up front and it may stay that way. It would be really nice to drop all the original controls and switch to very simple levers and throttle and run a cable operated front master cylinder, but not quite yet. Right now there's a more modern honda mc on the bars, but it's not pretty. For now, both throttle and clutch cables need to be shortened by about a foot and I'll need to arrange for brake lines.

A couple bits of advice: Have your swingarm rebuilt (ex. by hondaman). The off-the-shelf bronze bushings I bought have tons of slop, though my pivot bolts are stock spec. I'll probably find myself tearing the swingam off the second I actually ride this thing. Also, handlebar makers might say that the clamp spacing on their bars is 4.75", but that doesn't make it so.. the emgo superbike bars run more like 4.5" and start curving up before they're clear of the clamp.

Also, if anyone has experience using pj1 satin black engine case paint, let me know. It was a joy to use when painting the cases, but now it just seems to come out in flakes. I have 5 cans from two different vendors and spoke with the wonderful but miffed folks at pj1 and can't figure out why it's coming out like garbage.

I remember when I wanted to have this bike done back in the spring. It's been a ton of work and some dumb luck, both good and bad, but when it's done it's going to have been earned, not bought. There's been very little cutting and lots of cleaning up. I just pray the motor doesn't explode when I finally try and start it

« Last Edit: September 04, 2011, 01:46:51 AM by luceja »
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline Cheffish

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Re: James' 77 550f.
« Reply #78 on: September 04, 2011, 09:15:32 AM »
How did I miss this thing? Very cool. subscribed!

Offline fastbroshi

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Re: James' 77 550f.
« Reply #79 on: September 04, 2011, 03:30:18 PM »
Can you show us a pic from side showing the pipe's clearance from the axle?  Inquisitive F owners want to know.   Why don't you throw in a couple pics of that little Hawk too :)
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Offline luceja

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Re: James' 77 550f.
« Reply #80 on: September 05, 2011, 10:56:06 AM »
Can you show us a pic from side showing the pipe's clearance from the axle?  Inquisitive F owners want to know.   Why don't you throw in a couple pics of that little Hawk too :)

It's hard to explain - since I haven't cut anything yet, it's still covering the axle, but what I'm planning on doing would leave it exposed. Also, positioning (like how it's rotated) is determined by a bracket that doesn't yet exist, it's held on by bungee there.

It has two kinks down at the collector, and I'll take a pic, but it goes like this: The OD of the 550f collector is 2 1/4. The OD of the end of the muffler is also 2 1/4 for about an inch and a half. Then it kinks up about 5 degrees and reduces to an OD that is exactly the ID of the 550f collector, and goes for another an inch and a half. Then it bends up another 5 degrees and the megaphone starts.

I'm planning on cutting the first 2 1/4 OD section and the first 5 degree bend off of the muffler, about 2 inches. This will allow the slightly thinner section of the muffler to slide right into the 550f collector, and it appears that the remaining 5 degree bend will point the muffler directly along the stock muffler bracket that hangs off the frame. Also, cutting those two inches off looks like it will make the muffler short enough to leave the axle bolt totally exposed.

I guess the point is that you could leave these mufflers intact (except for the bracket) and just connect the muffler and the header.. the 550f exhaust gasket slips right over both of them, all you would need is a band of metal and a clamp... or you could shorten it and have them slip together. Either way since you're doing the bracket you can determine  the rotation of the muffler and it's clearance.

As for the hawk, it's a doozie. Part of me thinks I should sell it when the 550f is done, but I know I'd regret it. It was the first bike I ever wanted.

« Last Edit: September 05, 2011, 10:57:54 AM by luceja »
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline luceja

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Re: James' 77 550f.
« Reply #81 on: September 08, 2011, 11:12:56 AM »
I've become one of those people who can't get the cam chain and sprocket onto the camshaft on a 550. I've had the head on and off more than 10 times trying to figure this out.

Followed Gordon's instructions and all other instructions I could find (but only one person noted that you have to have the cylinders raised about 1/2" to install the tensioner) New chain, appears to be on crank teeth correctly, rotated crank to make sure there's no bunched kinks, confirmed chain is going between front slipper and the case (not in the middle) and that front slipper is facing forward and up, tensioner is slackened to the max and locked there, camshaft seated in the head, head all torqued down. I can get the chain on the cam sprocket easily enough but it's taking way too much prying force to pop the sprocket onto it's lip on the camshaft. Killing me here.

On the bright side, this is only something I'll have to figure out once.

« Last Edit: September 08, 2011, 11:16:54 AM by luceja »
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline luceja

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Re: James' 77 550f.
« Reply #82 on: September 08, 2011, 11:17:54 AM »

Can you show us a pic from side showing the pipe's clearance from the axle?  Inquisitive F owners want to know.   Why don't you throw in a couple pics of that little Hawk too :)

broshi, I'll take a pic for sure when it's actually mounted up!
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline fastbroshi

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Re: James' 77 550f.
« Reply #83 on: September 08, 2011, 02:36:06 PM »
  I'm a big fan of the single-sided swingarm in general.  I guess Honda killed the Hawk since it didn't sell well, but you wouldn't think it when you see all these people out racing them and such.   In fact I've never heard a bad review.   I finally got the chance to see one in person a couple weeks ago and was astounded at how slim that twin allows them to be.     
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Offline luceja

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Re: James' 77 550f.
« Reply #84 on: September 09, 2011, 02:56:58 AM »
My understanding of the history (and I'm sure there's more qualified people to comment on this..) is that they didn't make the outright power that honda's 4's did (it's like 60 to the cbr's 90 hp) and weren't cheaper for it. Looking at the monster's popularity, I guess honda was just a little to ahead of the curve on the naked v twin sportbike approach.

My issue with a more modern bike is this - when I throw around my 400f, I feel like it communicates it's limits with lots of warning - I can have fun at much lower speeds. The thing with the hawk is that I keep pushing it and it doesn't give any indication that it's near it's limits, which gets scary when I actually reach them, and inputs are much more severe, both braking and throttle. So part of me likes the little 400 more, but there's nothing like really dropping deep intp a good corner on the hawk and throttling out - it can handle so, so much more commitment than I can offer. Obviously a good rider could push the 400 much harder than I could push the hawk, but it's just about my experience at my level.
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline fastbroshi

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Re: James' 77 550f.
« Reply #85 on: September 09, 2011, 03:15:57 AM »
  You'd think Honda would've noticed the market trend 5 years after the Monster's intro and responded with an updated Hawk of some sort, like a stripped Superhawk 996.  They could've pulled a smaller displacement twin from somewhere and offered a small and big displacement, running step for step with Ducati. 
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Offline db22

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Re: James' 77 550f.
« Reply #86 on: September 09, 2011, 06:50:02 AM »
Really enjoying this thread -- subscribed.
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I may be goin' to hell in a bucket, but at least I'm enjoyin' the ride. . .

Offline luceja

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Re: James' 77 550f.
« Reply #87 on: September 09, 2011, 11:54:41 AM »
  You'd think Honda would've noticed the market trend 5 years after the Monster's intro and responded with an updated Hawk of some sort, like a stripped Superhawk 996.  They could've pulled a smaller displacement twin from somewhere and offered a small and big displacement, running step for step with Ducati. 

Yup, but suzuki totally picked up the slack with the sv650. Honda has a big hole in their lineup right at the sv650's price - honda jumps from the $4k cbr250r to the $12k cbr600rr. Even the monster fits in that space.

What's interesting is that it looks honda is still selling the hawk twin in the form of a touring bike - the $12k nt700v.

In project related news, pistons are on the rods, cylinders and head are on and torqued down. The damned cam sprocket and chain are finally on the camshaft.

Now that I've torqued the head down, I'm experiencing a pang of panic that I left a piston circlip not fully pushed into it's groove or something dumb like that.

There's also a kind of stupid risk with the cylinder honing - the pistons and cylinders came with the cylinders honed by the previous owner. The pistons, rings and cylinders all spec'd out and the crosshatching looks consistent and at the right angle, but it would obviously be safer to hone them again, but there they are, impatiently assembled as-is.
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline luceja

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Re: James' 77 550f.
« Reply #88 on: September 17, 2011, 08:18:44 PM »
Can anyone reading this ID this part as being a 750f rear caliper/bracket? It looks different from any I've seen. I need a 750f caliper and bracket - http://cgi.ebay.com/ebaymotors/76-HONDA-CB750-CB750F-SUPERSPORT-CALIPER-REAR-B-1-/330579822689?pt=Motorcycles_Parts_Accessories&hash=item4cf817c861#ht_500wt_1182
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline bluesmoke69

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Re: James' 77 550f.
« Reply #89 on: September 19, 2011, 10:07:08 PM »
Does not look like my 1976 CB750F back brake caliper. Check out my build on the second page I think. Good luck with your project.
« Last Edit: September 19, 2011, 10:12:17 PM by bluesmoke69 »

Offline Retro Rocket

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Re: James' 77 550f.
« Reply #90 on: September 20, 2011, 01:01:18 AM »
Quote
It may need a more solid brace if the back is flexing without the stock arch.

It WILL need bracing, your shocks now have nothing to stop sideways or up and down movement of the frame at all, thats the reason for the stock brace in the first place....
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Offline luceja

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Re: James' 77 550f.
« Reply #91 on: September 20, 2011, 02:05:41 PM »
Quote
It may need a more solid brace if the back is flexing without the stock arch.

It WILL need bracing, your shocks now have nothing to stop sideways or up and down movement of the frame at all, thats the reason for the stock brace in the first place....

I figured/was hoping the upper shock mounts were so close to the main frame bracing that the pressed rear arch wasn't critical, but I'm not surprised to hear that's not the case. I'm curious if people who remove that arch and weld a rear hoop in have flex problems. The stupid thing I did was have the frame powdercoated before really thinking the frame through. At the time I didn't have access to a welder; now that I do, I would take a different path. As it is, I'll have to come up with something strong going across the frame using either the shock mounts or the two holes at the end of the frame, though I think it'd be hard to design something that has the rigidity of the stock arch. I studied mechanical engineering.. I should know better.
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline luceja

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Re: James' 77 550f.
« Reply #92 on: September 20, 2011, 02:10:12 PM »
Does not look like my 1976 CB750F back brake caliper. Check out my build on the second page I think. Good luck with your project.

Agreed, it doesn't look like any I'd ever seen, but I wasn't sure if one year had a variation. Thank you!
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline kendo57

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Re: James' 77 550f.
« Reply #93 on: September 21, 2011, 08:59:23 AM »
The standard brace behined the shocks is pretty weak , just a thin pressed sheet to hold the
rear gaurd. The rear gaurd is probably stronger. I think most of the stiffness comes from the
brace at the front of the shock mounts.

Offline luceja

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Re: James' 77 550f.
« Reply #94 on: September 27, 2011, 07:59:21 PM »
It runs. Getting it running was quite a chore. Had a few days of trying to figure out an electrical bug that was preventing the starter solenoid from engaging (still don't know what fixed it... I keep having no voltage at either the front or rear light fuses, and nothing after that works, now the rear is out) had the carbs on and off and on and off dealing with overflow and getting the float needles to actually stop gas. Once everything was assembled again, timing, valves, and a bench sync set, it started right up and ran splendidly, but leaked oil heavily from the hg. Turns out I sort of forgot the oil passage o rings, so spent last night doing a top end teardown to put them in. Once it ran with a little less oil leaking, I put enough parts on the bike like a folded towel held on with a bungee for a seat, or a non functioning tail light electrical taped to the frame) temporarily to take it out today and have some fun seating the rings.

The muffler hasn't been cut to fit yet and I don't have a bracket fabbed up, so I had a muffler that popped off and hung by ties for a few blocks until I fit it a bit more solidly and then hit the next problem. At first, it runs gloriously healthy, and then after a few minutes, starts to bog and eventually will just die between shifts and won't catch again for a few minutes. The problem doesn't seem to be electrical- the starter is cranking very healthy. Then I noticed gas leaking out of the airbox drain pretty heavily. Seems like the carbs are flooding again.

Either the damn needles aren't seating, or when I set my float heights, I misunderstood the two points that are supposed to be 22mm apart- I was surprised that all of my floats were more like 27mm, which makes me think the floats were fine but I was measuring wrong. More research, more pulling the filter/filter box/airbox/boots/throttle cables/carbs/bowls.

Worst part of whole project: getting float bowl gasket/o-rings in place. Best part of whole project: first time I found out that 550's rip.
« Last Edit: September 27, 2011, 08:01:22 PM by luceja »
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline Retro Rocket

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Re: James' 77 550f.
« Reply #95 on: September 27, 2011, 08:05:19 PM »
The standard brace behined the shocks is pretty weak , just a thin pressed sheet to hold the
rear gaurd. The rear gaurd is probably stronger. I think most of the stiffness comes from the
brace at the front of the shock mounts.

You may think its weak but its not and its necessary, { if you want your bike to handle as it should| . The shocks and frame at the back will twist without it, so its not only there just to mount the guard. The front brace on the guard isn't all that substantial either but it does its job and much more deflection is noticeable without it.....
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If You can't fix it with a hammer, You've got an electrical problem.

Offline paulages

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Re: James' 77 550f.
« Reply #96 on: September 28, 2011, 11:38:13 AM »
The standard brace behined the shocks is pretty weak , just a thin pressed sheet to hold the
rear gaurd. The rear gaurd is probably stronger. I think most of the stiffness comes from the
brace at the front of the shock mounts.

You may think its weak but its not and its necessary, { if you want your bike to handle as it should| . The shocks and frame at the back will twist without it, so its not only there just to mount the guard. The front brace on the guard isn't all that substantial either but it does its job and much more deflection is noticeable without it.....

My frame has the stock brace still, though I think the swingarm bracing is more important. When I was last dynoing my 550, you could watch the swingarm flex and the rear wheel float to the right when approaching 60+ HP. Granted his engine is stock, but still... good lesson in frame stiffness.
paul
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Offline Retro Rocket

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Re: James' 77 550f.
« Reply #97 on: September 28, 2011, 08:55:11 PM »
Quote
When I was last dynoing my 550, you could watch the swingarm flex and the rear wheel float to the right when approaching 60+ HP. Granted his engine is stock, but still... good lesson in frame stiffness.

I was just reading this in your other thread. I am using a bigger swingarm, and after reading that,  i think i will also have it braced.
The rear brace on the frame stops lateral movement caused by suspension movement.... ;)
750 K2 1000cc
750 F1 970cc
750 Bitsa 900cc
If You can't fix it with a hammer, You've got an electrical problem.

Offline luceja

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Re: James' 77 550f.
« Reply #98 on: October 01, 2011, 02:21:06 PM »
OK, so figure this. Carbs were flooding into the airbox, which was frustrating because I had already taken the time to hang the carbs and filled them without the bowls and held/opened/shut the float needles to check their sealing, but when installed they were still leaking so I took the filter/airbox/throttle cables and carbs off again. Looking for other causes, I found all four drain tubes were solidly plugged at the ends, but that still doesn't explain flooding. With the rack hanging and the bowls still on, I found one carb was still overflowing, so I checked the float needle and seat while in the carb, the needle and the seat o-ring sealed fine, the float was moving smoothly as could be and was set to 22mm, so I took the seat/needle out, put the seat on the end of a hose full of gas, pushed the needle in gently and confirmed for absolutely sure the needle was sealing. So what the hell?

I remembered a thread on here where someone found their overflow tube was cracked, and bingo, it was cracked, which would allow gas to leak down the overflow (which was plugged anyway). I have spare carbs, and the first bowl I took off also had a cracked overflow tube. What the hell with these things? I finally have a good one on (even though it's not correct left/right) and after assesmbly again, the bike runs fine with no leaking or overflow now.

What is mystery to me is that even if the problem was a cracked overflow tube, why would that flood up into the airbox? Wouldn't the float still rise when the gas got to a certain level, before rising up through the carbs, and seal the needle? All's well that ends well, but I don't like mysterious solutions.

Now I need to figure out the electrical demons - without changing anything to my knowledge, the main circuit worked, then cut when trying to start, now I can't complete the circuit the rear brake light is on. I suck at wiring.

Last problem I'm trying to resolve is light oil leaks at the head and cylinder base. Both sides of the hg were surfaced by a machine shop, new gaskets and o rings, so I'm thinking the oil passage o-rings I used were too small. Super frustrating. Wish I did oil bypass lines.

On the up side, the bike runs well and three of the plugs are a nice tan, one is sooty so I'll play with the idle mixture - if I leave all the plates off the supertrapp, it's delightfully loud but a lots of off throttle popping - lean, right? With about half the discs on the muffler the popping dies down.

I have a set of 40 slow jets and 100 mains so I can compensate a little bit if it's on the lean side, which might make room for pods or stacks or something less cumbersome to dissemble/assemble.

On another note, pj1 engine case paint seems pretty resilient to gas leaks.
« Last Edit: October 01, 2011, 03:15:02 PM by luceja »
'75 cb400f, '77 cb550f , CB160 road racer, '88 Hawk GT track bike, FZR400 race bike, and a bunch of old hondas in boxes.

Offline lucky

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Re: James' 77 550f.
« Reply #99 on: October 01, 2011, 04:58:07 PM »
Handlebars are silly? Look like regular comfortable handle bars to me.