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To make a long story short I crashed my 175. Just for the record my roomate (agreendrop) also crashed his 350 in the same turn. We are both fine, he honestly only has a scratch, and I have a few bruises. He got lucky and only bent his brake lever. I however need new forks and front wheel. I have a friend who is selling or parting out his 360. How much work would it be to get his front end on my bike. Just wondering cause he only wants like 200 bucks and it still ahs lots of good parts on it.
 

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Really hard to say...could be as easy as bolting it on. Could be as difficult as modifying the stem, mixing and matching new tapered bearings, and making new spacers for the wheel.
360 is a disk brake front end isn't it?

I've got a CB550 front end on my 175...required that I shorten the stem, mix two sets of bearings, a couple of spacers for the axle and a brake stay. And even at that I had to fudge the lower bearing which is 0.5mm too small....as you just can't get the proper bearing to fit the 550 lower stem and the 175 lower neck. Usually doesn't get more difficult than that.
JohnnyB
 

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see, i dont do it that way. i grind the weld, press out the stem, then grind the weld off the transplant stem, then swap em out. then reweld it. that way, you dont need to fuck with mixmatching bearings and shortening stems or putting in shims and crap like that. that is of course if the stems fit the lower triples. but from 350 to 550, 500 and 750, they do. the lengths are different, but the taper is the same. so it works. also, the early 360 had a drum. sounds like a corner i want to stay away from!

i need a 550 rear wheel for my k model, anyone??


jc
 

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I might have a rear wheel joe. unfortunately I can't remember and most of that stuff is in maine still. but I'll check next time I go, unless you need it sooner.
 

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Joe...that won't work on a 550 to 175. Stems are too different in length...and the bearings have to fit BOTH the stem oD and the neck ID. So yes you still have to screw with mixing and matching cause the 175 neck ID is different. Stem has to be cut in the middle and TIG'd cause you can press it far enough down into the lower clamp without hitting the tapered section of the stem and having it fall right through the hole.
In some cases I just mill my own clamps and make it work.
JohnnyB
 

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hey jeremy, im going to try and straighten it tomorrow. if you think of it when you go. mines nice and clean. just a little bent. so id like a nice clean one thats not bent. 100 on ebay, plus shipping. rip off.


jb, i thought the stem of the 175 fit the 350, so it should fit the 360 also. so my trade might work. going up to the 500 etc should work too, at least i thought it would siince it works the other direction. (im talking about your scenario) although i could be totally wrong. i thought aaron was running a 350 front end on his 175. but he might have gone through what you did to get it to work. maybe the 350 stuff is just blessed that way. the reason i like to do it that way is so i dont have to try to remember what bearings to buy. i just think if it as a 350 honda, so thats what i get. instead of having to remember a 750 top, a 450 bottom, etc etc etc....swapping stems resolves the length/spacer issue. since youre using a stock length. this is of course takes into consideration the thickness of the top clamp is close. (i thought it was actually thin where the stem comes through and the nut goes on) the bottom isnt such a big deal, as long as it can press in. and then with the weld, youre good to go. ive been told theres no reason to even weld them since they are clamped and bolted. (but like chris has said to me, if i think im better than a honda engineer, i should apply) so i weld em back up. anyway, im bored now.

me
 

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Joe,
Below is a copy of all the notes I have on 175 fork swaps. Problem is that the 175 uses a funky 48.5mm ID on the neck (top and bottom). And I couldn't find bearings that would fit the 350/550 stem and still fit the 175 neck ID. I'm talking tapered bearings...it's possible it could be easier using OEM ball bearings.
Like you say...since the 350-550 stems are same OD's but different lengths...instead of cutting a 550 stem, you could probably press in a 350 stem if they are shorter...easier than cutting a 550 stem.

Here's what I came up with doing the 550/4 to 175 swap.

____________________________________

Forks

Forks being used are 1974-78 Honda CB550 SOHC fourcylinder 35mm tubes


Fork tube diameter 31mm (stock CB175)
Source for roller neck bearings - Dennis Kirk, Pro-Flow
Stock Neck Bearing measurements: Cup OD top and bottom 48.5mm/1.91"
Stem dia: top - 25mm bottom - 27mm


CB350 and CB550 Stem diameters: Top - 26mm Bottom - 30mm
For CB350 or CB550 front fork conversion use:
Kit SSH750 for the top bearing (kit contains one 26x48x15 and one 30x50x15)
Kit SSK100 for the bottom bearing (kit contains two 30x48x13) must use at least 0.5mm shim under lower bearing.
So far I have found no kit that contains the needed 26x48x15 and 30x48x14) note: 13,14 or 15mm thickness should work.

Notes:
Three quarters of an inch must be removed from the length of the stock CB550/4 steering stem to work in the CB175 neck. About 0.5 mm shim must be placed under the lower tapered bearing for lower clamp to clear the bottom of the CB175 neck. Grinding was also needed on the bottom of the CB175 neck to provide turn clearance for the lower CB550/4 fork clamp.

CB550 fork uses 190cc (6.5 oz) of oil (see weight recommendation below)
CB350 fork uses 200cc (6.76 oz) of 10wt oil in stock form.

7/17/00 - Presently I am using @ 8oz of 15wt fork oil

Replace the fork springs if they are shorter in free length than;
350/4 = 16.38 in. (416mm)
400/4 = 18.84 in. (479mm)
500 - 550/4 16.73 in. (425mm)
fork oil stock 350/4 4.2 oz. (125cc) of ATF
400 - 500 - 550/4 5.4 oz. (160cc) of 10w - 30 oil
From this chart if your 550/4 springs are shorter than 16 3/4 inches you need new springs. Also stock most ran 20w oil, for racing you might want to try 30w. The pictures in my book show forks with a moving damping rod. I don't think the 4 cylinder forks have that. Most of the Honda forks of that era had fixed damping, just a pipe inside the tube with holes drilled in it. A few model Honda forks had a moving damper with what looks like a ready-rod coming up from the bottom attached to the top fork cap.
 

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what a pain in the ass. i thought all the steering head bearings were freakish in size. not just yours. hmmmmm. intersting though.

jc
 

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ah, see, the length scared me from trying to use it. i just tried to figure out the easiest way to get from a to b. there also might be a cearance issue on the bottom clamp too, but i cant remember for sure. i thnk i just ground the frame instead. there was plenty of room there. i do know the sterring stops dont work on the swap so i had to make up new ones.

jc
 
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