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Re: Yet another 1976 Supercharger project
Posted: Wed Aug 10, 2011 8:26 pm
by calif wingnut
ZZZZZZZZZ
Re: Yet another 1976 Supercharger project
Posted: Thu Aug 11, 2011 12:08 pm
by Qui-gon
Calif Wingnut wrote:ZZZZZZZZZ
Is that you sleeping on the job again Jeffo? Shouldn't you be putting the SEI back together?
Nice pipe, when I get done the inner cone will match the engine colour
Re: Yet another 1976 Supercharger project
Posted: Fri Nov 11, 2011 5:38 pm
by Qui-gon
Been a while doing other things so time for a mini update:
Remounted the fuel pump on the back wall of the shelter as I wasn't happy with the original placement. Seems to work ok even though the lift specification for the pump is close to the max:
Capped the end of the RH camshaft with a hand crafted aluminium cover. Looks a lot cleaner now:
Took a while to get the idle right. Just a small amount of surging caused by puddling on the manifold, but it runs really well so far.
Re: Yet another 1976 Supercharger project
Posted: Sun Nov 13, 2011 2:05 pm
by socrace
Hey Qui-gon,
Finally got to check out your build, very nice job!
Especially like the small block chevy paint theme! And the seat, where did you source it?
The surging idle you mention could be something typical with some blowers, aka "blower roll". Caused by interaction between vacuum and blower efficiency; the vacuum in the manifold basically sloshes around like water in a bathtub. There is sometimes a vacuum operated bypass valve inside the blower body that can help. It could be that things are made worse by the design of the manifold, with that depression in the middle.
Re: Yet another 1976 Supercharger project
Posted: Sun Nov 13, 2011 6:30 pm
by Qui-gon
Thanks for the complement. Its more or less finished but hey there is always something left to do. I am going to replace the starter switch assembly with a relay. I already burnt the switch out by a combination of old age and a higher power halogen headlamp. I also need to address the neutral switch. It is an led which is part of the dash and requires less of a ground to illuminate than the standard filament bulb. At the moment the led is full bright when in neutral and half bright when in gear! These switches are notorious for being leaky so another small relay will do the trick.
On the way to Alaska in the summer I called in to see Bill Bushling, one of the guys responsible for the original GL super charger "kit" back in the 80s. He gave me a few good tips and ideas for improvement. His description of the surging was "puddling" due to the manifold shape and fuel accumulating on the floor of it. When I first started it it was really noticeable when warm, now it's not as bad.
The seat Is a Darkwing seat from a guy in Florida. It is not a bolt on accessory and needs some individual fitting requirements. There is plenty of extra material left along the bottom edge which needs trimming off but it's very sturdy when bolted up. I am still not sure about the look but a few here seem to like it.
Re: Yet another 1976 Supercharger project
Posted: Mon Nov 14, 2011 3:09 am
by Charlie503
Nice work and a lovely bike.
I wish I had the time and cash to do a full rebuild like this. Keep up the good work
Re: Yet another 1976 Supercharger project
Posted: Mon Nov 14, 2011 1:12 pm
by Qui-gon
Re: Yet another 1976 Supercharger project
Posted: Mon Nov 14, 2011 8:01 pm
by sunnbobb
Very nice work. Very.
Re: Yet another 1976 Supercharger project
Posted: Tue Nov 15, 2011 11:28 pm
by gregforesi
That bikes's a friggin beauty.
Regarding the brakes - Have you considered upgrading the front master? There are a couple out there with smaller pistons for a better mechanical advantage.
BTW - At one point Randakk was talking about adding a rev limiter to his blower bike because it wound up so fast. I don't know if he ever found one for it.
Re: Yet another 1976 Supercharger project
Posted: Tue Nov 15, 2011 11:40 pm
by robin1731
gregforesi wrote:snip
BTW - At one point Randakk was talking about adding a rev limiter to his blower bike because it wound up so fast. I don't know if he ever found one for it.
Dyna makes one that works very well and is easy to wire in.
Re: Yet another 1976 Supercharger project
Posted: Tue Nov 15, 2011 11:43 pm
by Fred Camper
I agree that you need a rev limiter, it is just a mater of time before you miss a shift and on that bike a missed shift cannot be stopped fast enough with human response from what I have heard. No difference than running nitrous I think.
Re: Yet another 1976 Supercharger project
Posted: Tue Nov 15, 2011 11:46 pm
by robin1731
If I were to do a blower or nitrous (my preference of course is nitrous), I would add a few more pounds of pressure to the valve springs too. Just for a little insurance.
I know Qui-gon's bike is done already. I'm just thinking about future builds.
Re: Yet another 1976 Supercharger project
Posted: Wed Nov 16, 2011 1:15 pm
by Qui-gon
All good points:
sunnbob is that Quake logo derivative you have now?
gregforesi wrote:That bikes's a friggin beauty.
Regarding the brakes - Have you considered upgrading the front master? There are a couple out there with smaller pistons for a better mechanical advantage.
BTW - At one point Randakk was talking about adding a rev limiter to his blower bike because it wound up so fast. I don't know if he ever found one for it.
I have been looking at the front master cylinder as a way of increasing the effort ratio. Randakk's is a very good price too. I have been looking at used off later bikes
Rev limiter is a good idea though.
robin1731 wrote:
snip
Dyna makes one that works very well and is easy to wire in.
I will check that out thanks. I have the shift light on the dash set to 8k5 but that won't help if I miss a gear!
robin1731 wrote:
snip
I know Qui-gon's bike is done already. I'm just thinking about future builds.
I wish! It will never be finished! There are many upgrades in the pipeline. I want to try the 78 engine I have with the softer cam soon. I am also looking at direct injection as an option and controlling all of it electronically. All of it depends on our circumstances here and whether I export the bike back to Europe when we leave.
Re: Yet another 1976 Supercharger project
Posted: Wed Nov 16, 2011 11:06 pm
by robin1731
This is when DOHC's would really be nice. You could play with valve overlap. You could also play with exhaust duration. With a normally aspirated engine these both help but with any power adder, blower, turbo, nitrous, those little changes can be huge.

Re: Yet another 1976 Supercharger project
Posted: Wed Nov 16, 2011 11:18 pm
by robin1731
Go here to check the Dyna rev limiters. The DRL-300 is the one that would work best. The 400 would work too but it has the two step on it. Although fun it isn't needed on a street bike.
http://www.dynaonline.com/skins/product ... v_limiter/