75 CB360 - bad omen "yatagarasu" build

Cursh

Loves Stock Airboxes
I honestly think all you are doing is removing material that isn’t being used for strength at all. The ribs at the outside are doing most of the heavy lifting (where the sawtooth marks are) and they are held parallel by the top brace left over after machining.

If you look at the failure point on the example in the last post, It doesn’t look like the break line is an area where you’re interested in removing material. That’s a good sign too.
 

irk miller

You've been mostly-dead all day.
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Sonreir said:
Yeah... I think I'm picturing it now?

Crank turns the primary and outer basket and power is transferred to the main shaft through the plates and inner basket... right?
Exactly. When the plates engage, both inner and outer turn together.


Sent from my iPhone using DO THE TON
 

MiniatureNinja

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First ride since the rebuild today. Unfortunately I could not for the life of me get my cheap Chinese knockoff grimeca master cylinder to bleed so I had to resort to a backup.

I started the day syncing carbs and bike responds great throttle now, quick revs up and down... I didnt rev it unloaded above 5k. Got it out in the road and did a couple of acceleration and deceleration on engine up to about 7k, then let it rest for a few and then back out for up to 9k runs. Gonna check clearances then do runs up to 11k tomorrow.

Gonna have to mess with some jetting, bike had good acceleration but there are two flat spots, one at 3k and one at 6k

Also thingsnot go so well when I forgot to put the front bolt in the brake stay and as I hit the rear brake it jammed the stay into the road and luckily I have a carbon fiber actuation rod so it ripped it apart instead of locking up the rear tire at speed. No problem.. both can be easily fixed and I'll have rear brakes again.

I love this bike!!!!!!!
 

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Alex jb

New Member
Top work, glad to see it out in the wild!

My little 175 may only have 15ish hp but I love riding the heck out of it, can’t wait to get my new engine finished and in and (hopefully) 20+hp.
42 hp sounds like a lot of fun (as long as you have the tyres and brakes for it!
 

MiniatureNinja

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pidjones said:
I had a rear brake lock up at speed on a TR6C chopper. NOT FUN! BTW, I think that color is perfect.
I talked to Isaac at Speedy Siegl Racing (where I got the brake stay from) and told him what happened, I assured him it wasn't his fault. But I told him because the brake stay actually jacked into the road, spiking the rear of the bike up before the drum housing rotated enough for it t be out of the way (also shattering my carbon fiber actuation rod)

the brake stay has some scuffs, but it's not bent, it's perfectly straight and this sucker is TOUGH! https://www.speedysieglracing.com/honda-parts/honda-cbcl-350-550-rear-brake-arm
super light weight, and in my humble opinion - they look 10x better than the other offerings out there
 

crazypj

Split personality, I fake being smart
Now you have exhaust on I can see your going to need larger secondary main jet. try a 120 instead of the 115 I fitted. Because exhaust length becomes pretty critical you may need to get some 117.5 and 122.5 (never had one needing more than 125 even with short 'big bore' pipes) Have you adjusted fuel screw? Try 3/4~1 turn out. Alternatively, try holding at rpm where your having a problem (3K first) kill motor without closing throttle and pull plugs to check colour. Do it again at 6K. It may be leaning off too much at 3K or reverse pulses from exhaust length could be causing problem? Pretty sure it's 'fixable' though
 

MiniatureNinja

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crazypj said:
Now you have exhaust on I can see your going to need larger secondary main jet. try a 120 instead of the 115 I fitted. Because exhaust length becomes pretty critical you may need to get some 117.5 and 122.5 (never had one needing more than 125 even with short 'big bore' pipes) Have you adjusted fuel screw? Try 3/4~1 turn out. Alternatively, try holding at rpm where your having a problem (3K first) kill motor without closing throttle and pull plugs to check colour. Do it again at 6K. It may be leaning off too much at 3K or reverse pulses from exhaust length could be causing problem? Pretty sure it's 'fixable' though
After second runs up to higher RPMS it's doing muuuuuch better - still a flat spot there at about 3k, so will have do break out the gunson color tune kit (i would rather use than that plug chops)

I am waiting on extra $$ for a good quality reverse cone muffler, and will be doing a 2-1 collector to the reverse cone, extending the exhaust another about 20 inches - should help too - pipes are stock diameter for the first section of the CJ pipes then internally baffled 1 5/8" pipes that are 20 inches long - will try the larger jets tomorrow maybe, or probably this weekend
 

crazypj

Split personality, I fake being smart
It may be better to just live with it until you get exhaust finalised as it's highly likely you'll have to do it again. Colortune is really only for idle mixture (and vehicle emission inspection), under load they heat up way too fast. If engine isn't under load it's almost certain to show a rich mixture
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

Ah ok gotcha.

So I went for some more runs, dead spot seams to be more like 5k and only when light on throttle... if I give it all the throttle (and lean over the tank to keep the front end down) it pulls like an sr71
 

crazypj

Split personality, I fake being smart
LOL, Almost forgot, you need around 200miles/2 tanks gas before doing major carb tuning. Very few people believe just how quick a 378 is - until they ride one. My buddy Brendon has surprised a lot of people with $20,000+ bikes getting away from lights way quicker than anyone expected (me included a few times)
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

Yea flat spot seams to be going away actually... this morning on the way to work it was just smooth all the way through. I'm gonna swap sprockets to the stock size 34t to see if it's the engine or the 35t sprocket that is trying to through me off the bike. Haha
 

crazypj

Split personality, I fake being smart
You could probably use a 33 or 32 and lower cruising rpm.I don't think you can go smaller than 32 as chain contacts hub? (maybe it's 30t, been almost 30 yrs since I checked ?) I wouldn't even consider a 35 or larger with a 110 tyre, although I'm probably going to fit a 38 on 'Blue Bike' as it's got a 4.50 trail tyre on it and is going to be used off road sometimes
 

Sderbyshire

Into Sailing, classic Triumph cars and motorbikes.
Re: 75 CB360 - bad omen "yatagarasu" build

MiniatureNinja said:
Got some more badass lightweight aluminum for the bike today, courtesy of speedy siegl racing. nearly finishing touches on the exhaust
Those are nice.....
 

MiniatureNinja

Member
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Re: 75 CB360 - bad omen "yatagarasu" build

Well this sucks.

After getting better and better the more I ride it, I barely made it home the other night.
Bike ran great high RPM or WOT, but coming off a light or anything below 3k it wanted to die. I got home pissing off every car alarm and business owner on my street. left spark plug was wet, almost like oil fouled. Right plug was coffee brown

Is this bike running too rich?
Changed plugs, bike starts and runs great then about 10 minutes later similar symptoms. I'm afraid to ride it home again I'm leaving it at a friends house until I can get it sorted
 

crazypj

Split personality, I fake being smart
It may be a little rich, you neerd it running right to check though. For it to get worse after 10 mins, it may be ignition heating up? If you have a timing light you could check spark isn't breaking down. Otherwise, check all carb jets are tight, maybe vibration loosened something off? Carbs are still level? If the rear 'sags' it raises fuel level causing rich mixture. How many miles on it now? Did you fit new points? They may have closed up. Did you check battery voltage? When it's low bike 'drops' a cylinder
 

MiniatureNinja

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Re: 75 CB360 - bad omen "yatagarasu" build

So things I checked:
Battery voltage (because I've had these problems before) its and antigravity lithium 4cell. 13.4 volts running at 13.6
Rick's high output stater and regulator for lithium batteries too, so that checked out

Ignition coils are nice and cool actually, being out in the wind must help, even sitting over the headers they are cool to the touch.

I took carbs off and checked all, float was set st 25mm, not sure what it was supposed to be, I left it alone. They are on there straight and the boots are in very good condition.

Nearly every other bolt had vibrated off, had to buy new ones and drill them for safety wire, bike vibrates a LOT I think more than it used to... not sure what's up with that. Feels like I'm sitting on a gravel packer.

Points are original for 1975... I should probably replace them, but they spring back and gap is good. I'll have to time it dynamically to see what's going on for sure. I just dont have a center stand yet and dont want oil pouring out the left cover
 

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