Author Topic: fast track to getting on the road  (Read 1564 times)

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Tom Stark

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fast track to getting on the road
« on: June 18, 2007, 08:09:53 PM »
Just got back into bikes.  I had a 750 SOHC years ago, and just got a "rescue" one recently.  The story about it can be read at http://www.absolutetops.com/750Four/bike.htm  The bike was in BAD shape, but is starting to look good.  This one was truely pulled out of the crapper!  If I had known as much about it when I got it, as I do now, I would not have paid the $140 for it (delivered to my door).  I would have gone more like $50.  Anyway, when I am done, I will have under a grand into it, and it will be a cool bike.
Any comments or suggestions are welcome.
Tom Stark

Offline nickjtc

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Re: fast track to getting on the road
« Reply #1 on: June 18, 2007, 10:16:02 PM »
That's going to be an interesting project. Keep us in the loop, please.
Nick J. Member #3247

2008 Triumph Tiger 1050
1977 Suzuki GS750

"That which does not kill us reminds us to wear proper motorcycle clothing...."

SOHC steve

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Re: fast track to getting on the road
« Reply #2 on: June 19, 2007, 01:52:29 AM »
Welcome,looks like you saved that 750 from the scrap man for sure,well done.It was a very interesting read about all the undoing of all those "mods"and it really is looking good,well done.I loved the wiring harness that looked like a snake that just ate a pig comment  :o J ust as well you have welding and electrics experience...whats next a megasquirt injected 750 ;)
Cheers,Steve 

Tom Stark

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Re: fast track to getting on the road
« Reply #3 on: June 19, 2007, 05:15:22 AM »
Funny you should mention the megasquirt.  I have one on my 1962 Corvair.  Just controls spark at this time, fuel to come with the next motor.  I had considered MS for the 750, but there really is not that much room, and I am working my way up to a Goldwing.  If/when I get a Goldwing, I will MS that if it is not new enough to already have EFI.
I hope later today, (after work), to start the bike up again, and this time have the oil light, and neutral light, working.  I also want to let it run long enough to see if it stops smoking.  The smoke I saw could easily have been from having the motor off and rolling it all around.  Very easy for some oil to have gotten past the rings with all the moving the engine did.  We will see.  I am just glad things were close enough for it to start, has to be a good sign!
Tom

SOHC steve

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Re: fast track to getting on the road
« Reply #4 on: June 19, 2007, 03:32:37 PM »
     I had a look at your Corvair,Im a bit of an old car nut too,one of my future projects was to fit EFI to a smallblock Ford in my old Falcon Futura coupe,nothing new about that conversion I guess,but I had heard about the megasquirt system but never really known anyone using them over here in Australia.Sounds like a very economical way of going about it.
      The Honda would be great with EFI,but I think the charging system would need some work as well,they dont seem to be that good until about 3000 rpm.Still,it would look great to have a cafe style 750 with the efi sitting there,Im sure a few eyes would pop out of their sockets :o Please keep us posted with the progress...Steve

Tom Stark

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Re: fast track to getting on the road
« Reply #5 on: June 19, 2007, 10:45:48 PM »
If you are thinking about megasquirt, it is a good item.  Even the guys at F.A.S.T. respect it!  (talked to one of the FAST reps at the track, and he had good things to say about MS, still said FAST was better!)  If you want to buy anything MS related, you may want to check out Jerry at www.diyautotune.com  VERY helpful, and he packages everything for you to make it WAY easy to assemble the kits.  He also has assembled kits, but to me, building the kit is half the fun! 
Tom

SOHC steve

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Re: fast track to getting on the road
« Reply #6 on: June 20, 2007, 03:00:46 AM »
Thanks Tom,I had a quick look at that web site,LOTS of info! Sounds like a really flexible unit and the one stop supplier sounds like the way to go.I bet that guy from FAST was a little red faced admitting the MS was right up there :D One thing I hear about some aftermarket ECU's is that they can be effected by "noise"from MSD units etc...have you ever heard anything along those lines about the MS?...    First things first,I'll do my K6 rebuild (pretty much going to be a resto with minor performance and electrics enhancements) and then start getting into my cars again.The good news is my father in law is a retired electronics guru...with a little pleading I think he would enjoy working on this project as well ;D
                   Steve
« Last Edit: June 20, 2007, 03:06:43 AM by SOHC steve »

Tom Stark

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Re: fast track to getting on the road
« Reply #7 on: June 21, 2007, 11:53:19 PM »
Sorry I didn't get back to you sooner, been busy.  Noise CAN be an issue, but need not be.  Mount the ECU as close to the battery as you can, and wire directly to the battery.  Del City has a really neat item to mount up to 4 wires directly to the battery, it can be seen here http://www.delcity.net/delcity/servlet/catalog?parentid=789164&page=1 
Also, shield any wires you think may give you trouble, like the tach lead.  (A mic cable makes a good shielded cable.  Ground only one end of the outer shield.)
I have a noise issue with my Corvair, but it is not the fault of the MS.  I am running a GM 7 pin ignition, (no vac or centrifugal advance, all ECU).  I am using the GM module, probably should have used the VR circuit in the MS but oh well.  With an MSD blaster 2 can coil I never had a problem.  I changed to a hotter coil, an epoxy unit recommended for the GM ignition, and then I started having the noise problem.  It would cause misses, and timing jumps around 3500+ RPM under light load.  Under heavy load, the noise did not become an issue until higher up if at all.  I put in a digital Mallory box, (like the MSD).  I thought that would help.  It made no difference.  I then twisted up the VR wires as far as I could without unwiring a bunch of stuff.  That moved the noise up to 4000 or over, again under light load, heavy load is not a problem, or very little problem. 
I broke a starter nose and have to pull the drive line anyway to dig out the bits of starter to protect the bell housing, so I am putting in a 3.89 gear, (replacing a 3.55), and will pull a lot of the wiring and redo it with all twisted pair wires.  I think that will fix it. 
I know this post does not have anything about the SOHC bike, I am only posting this here, rather than sending it privately, because I think this info is of use to anyone thinking of a MS for their SOHC bike.