First build ever

I think you would need pipes coming either side of cylinders to make a nice looking underseat exhaust, both coming in from left just doesn't sound right?
 
crazypj said:
I think you would need pipes coming either side of cylinders to make a nice looking underseat exhaust, both coming in from left just doesn't sound right?
Yes unless two to one and run it oval
Under seat but that's prolly too extreme for me and this build
I don't think it looks too bad in the photoshop image having longer pipes like that
My seat is a lil longer than the bike in picture so that will help with the look


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The intake is sized for a 400 motor stock so you have to be very careful doing any mods. I tend to smooth it out slightly and unrestrict valve guide boss. The exhaust side is the restricted area, you can pretty much carve on it without hurting any flow (although it is possible to go too far it takes a lot of cutting). With a 378cc conversion everything works much better. The AG Bell books give a lot of information that works but David Vizard keeps up with later developments (I guess he 'invented' some of the stuff various racing engines use?)
 
crazypj said:
The intake is sized for a 400 motor stock so you have to be very careful doing any mods. I tend to smooth it out slightly and unrestrict valve guide boss. The exhaust side is the restricted area, you can pretty much carve on it without hurting any flow (although it is possible to go too far it takes a lot of cutting). With a 378cc conversion everything works much better. The AG Bell books give a lot of information that works but David Vizard keeps up with later developments (I guess he 'invented' some of the stuff various racing engines use?)


Yeah I was unable to find anything specific in his books for a 360 motor but
Was able to learn a lot and understand the theories and principles behind it

So I went with your advice and his theories and ended up with great looking head lots of work like 45+ hours into it stayed away from intake side just cleaned up some of the poop from casting and was able to use a pretty expensive piece of inspection equipment to port he match as.close I could
It's within a thou
Roundness and diameter
The exhaust worked
7eab1716c70b6d1167eda0d203978d4c.jpg
ccecb819b440932396714415038f2a37.jpg
9acb42f39578906fe8b3b45f0874da18.jpg

Gs850 Pistons had to have em
I'm hoping for solid results improvements


I just had new bronze guides driven
And last is new valves
86c7af13ea33f3f5aa9302d3ae10269d.jpg
7599d01fddc16ef975a24fd8dba1d44c.jpg
e95bc3345214914508800f57d4ff40be.jpg




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onefromexile said:
Yeah I was unable to find anything specific in his books for a 360 motor but
Was able to learn a lot and understand the theories and principles behind it

So I went with your advice and his theories and ended up with great looking head lots of work like 45+ hours into it stayed away from intake side just cleaned up some of the poop from casting and was able to use a pretty expensive piece of inspection equipment to port he match as.close I could
It's within a thou
Roundness and diameter
The exhaust worked
7eab1716c70b6d1167eda0d203978d4c.jpg
ccecb819b440932396714415038f2a37.jpg
9acb42f39578906fe8b3b45f0874da18.jpg

Gs850 Pistons had to have em
I'm hoping for solid results improvements


I just had new bronze guides driven
And last is new valves
86c7af13ea33f3f5aa9302d3ae10269d.jpg
7599d01fddc16ef975a24fd8dba1d44c.jpg
e95bc3345214914508800f57d4ff40be.jpg




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fb77929d490feafa0caf97c0a44199af.jpg




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45 hrs sounds a bit much but as you had some specialised equipment to match left and right I guess it's not too bad.
Long time ago (around 1980) I spent over 25 hrs doing just one intake on a GS550 then around the same to get the other 3 intakes matched (much easier when you have a pattern to follow) Turned out a stupidly fast bike after big bore conversion, frame welding, stock carbs bored oversize and a full race exhaist and cams (around 170 mph but not with me on it :eek: ) Honda VFR 750 had just been launched, it was great fun running away and hiding from them on what looked like a POS ;D 8)
 
crazypj said:
45 hrs sounds a bit much but as you had some specialised equipment to match left and right I guess it's not too bad.
Long time ago (around 1980) I spent over 25 hrs doing just one intake on a GS550 then around the same to get the other 3 intakes matched (much easier when you have a pattern to follow) Turned out a stupidly fast bike after big bore conversion, frame welding, stock carbs bored oversize and a full race exhaist and cams (around 170 mph but not with me on it :eek: ) Honda VFR 750 had just been launched, it was great fun running away and hiding from them on what looked like a POS ;D 8)
I spent way to much time on it but he is my first full build on a motorcycle
Even when I acquire and build more down the line he will be my prize my daily rider
I used a cmm inspection machine
I checked every surface ,angle , dimension , I've been so precise remember our ring gap and cylinder bore discussion??
I shopped around finally found a shop that can guarantee my specs wanted
I even had my gs Pistons polished perfect both same size but one is a lil less than a gram heavier
Overkill
I do want my 360 to be bad ass
I don't want to go extreme like cams I only have aluminum seats lol you know
I do plan on an upper oil mod
But I have an extra rocker box cover and such for that
I'd love to discuss more on
I've found micro pump that would be perfect for it
Vfr750 I just picked up a 94 it was free just had to pay gas to pick it up
I had a discussion going about using any of it on a cb750 roller I also got for free




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I've given a dedicated 'top end' oil pump a lot of thought over the years but decided against it every time. Modification plus better voil seems to have cured the 'problem'. I've stripped a few motors now that look better than when they were assembled.I am doing the external oil line bypassing filter on a couple of engines though.
 
crazypj said:
I've given a dedicated 'top end' oil pump a lot of thought over the years but decided against it every time. Modification plus better voil seems to have cured the 'problem'. I've stripped a few motors now that look better than when they were assembled.I am doing the external oil line bypassing filter on a couple of engines though.

I plan on running no external yet but still work on developing a system
Mostly for cooling the oil
Look at what I just dragged home
59cefd04c2f7df9217da2b448d3b4eec.jpg



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That motor is very under-stressed and over engineered. It never developed anywhere close to full potential. I would bump it to 500cc with later 500 twin parts ;)
 
crazypj said:
That motor is very under-stressed and over engineered. It never developed anywhere close to full potential. I would bump it to 500cc with later 500 twin parts ;)
Ohh do tell all
Turns out it's an 80' gs450 frame 80' gs450 engine too
Right now I cleaned up the wires they were melted together
Po was trying to run a single dual output coil wondering why wouldn't run and tried to silicone the bad intake boot
Definitely a lot of hacked work but I pulled it all off and went to simplifying
In needs one carb boot and fork seals few things but I can run it and use it while I build my 378
I'd like to eventually do a tracker brat
Versatile lil beast


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onefromexile said:
Ohh do tell all
Turns out it's an 80' gs450 frame 80' gs450 engine too
Right now I cleaned up the wires they were melted together
Po was trying to run a single dual output coil wondering why wouldn't run and tried to silicone the bad intake boot
Definitely a lot of hacked work but I pulled it all off and went to simplifying
In needs one carb boot and fork seals few things but I can run it and use it while I build my 378
I'd like to eventually do a tracker brat
Versatile lil beast


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Let me say further on the coil
I don't think it can be used on this bike because it has no points condenser
However I have seen a single dual output coil used on honda twin
So I'm a lil confused but
Will look into it further
I'm pretty sure I can use old singles on the gs


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It all depends on crank configuration. A 180 crank needs two coils but 360 crank can use a dual lead coil. Even then, two coils is actually better though
 
crazypj said:
It all depends on crank configuration. A 180 crank needs two coils but 360 crank can use a dual lead coil. Even then, two coils is actually better though
Back to the oiling
And my original build

What do you think about modifying a starter delete plug and fitting and bending a small pickup tube to sump oil
Through external cooler /filter to head While engine is on side stand or high rpm
I could even have on demand power before starting to avoid dry starts
This system will be totally independant from original oil /filter system
I'll be drawing low amps constant
And it will be sumping from left side of lower end
That way I'm not taking from the oil pick up and slinger
I'd use 1/8" inch copper lines fittings
To help with cooling further
The pump has its own intergrated controller and small enough to mount inside starter case shell and run lines out maybe easier to use starter nose
I have to show you the drawings
But it's by far the least power draw and smallest compact efficient system I've been able to come up with




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I was going to do something very similar. Drill a pick up hole just below where the baffle plate rod sits so it's higher than the sump pick up. That way the electric pump will never be able to drain sump (although oil in head will get to mains and big ends with back-flow/drain
 
crazypj said:
I was going to do something very similar. Drill a pick up hole just below where the baffle plate rod sits so it's higher than the sump pick up. That way the electric pump will never be able to drain sump (although oil in head will get to mains and big ends with back-flow/drain
That's what I was wondering
If it's not drawing away from oil pick up
And has its own cooler / filter and your adding oil with the volume of filter and cooler calculated
Really it's just to have no dry starts but also cooling good oil and filtering it should help and keeping the baths full
It's more or less an independent line bringing oil to the head gravity will bring it back down



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Yep, the problem 30+ yrs ago, there were not the choices available for miniature oil pumps or high efficiency electric motors. I looked at the filtration system as well, you cannot get better than centrifugal, any filter medium will always allow some particulate through.
A centrifuge forces any heavy particles to outside of filter bowl (OK, osmosis is a different matter but we are not trying to remove various elements from oil, just 'bits')
I have an oil filter article saved somewhere (found it a couple of days ago then 'lost' it again ::) )
 
crazypj said:
Yep, the problem 30+ yrs ago, there were not the choices available for miniature oil pumps or high efficiency electric motors. I looked at the filtration system as well, you cannot get better than centrifugal, any filter medium will always allow some particulate through.
A centrifuge forces any heavy particles to outside of filter bowl (OK, osmosis is a different matter but we are not trying to remove various elements from oil, just 'bits')
I have an oil filter article saved somewhere (found it a couple of days ago then 'lost' it again ::) )
That brings you back to the original system though
How dirty do you think the oil would be ??
If not as clean as oil coming from centrifugal then cooling oil is the only think rationally to make it better
For that I'm pretty sure you could tap and drill the right side case where there seems to be plugs all ready
And just run to cooler
And back to case


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Just posted some new 'Public Information Service' with oil filter pdf. and Honda Common Service manual pdf, you may wa't to read first and download second.
As for the clutch cover mod, that's what people are now doing.
If Photobucket sees sense and gives everyone their pictures back you'll find the info
 
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