1981 GS450E Rebuild

[pete]

Bummer Pete.

I am anxiously awaiting your HEI mod. I've seen this done a few times on XS's, but not a GS.

You can put the cable on without taking off the carbs. You have to rotate the throttle assembly with one finger and hold it open. That brings the slot up to where you can get the cable into it and then let it rotate back down to hold. I keep tension on the cable and then feed it up to the throttle.

Me too!

There are ones on here that people have done, but I haven't seen much on the way of details beyond Matchless' diagram in the very quick search that I did, so it's possible I've missed a detailed post or thread.

And I get ya with the cable I think. I tried holding the throttle open, but what you say about feeding up to the throttle makes sense... I had it in the throttle first, so I don't have enough slack to get it down onto the throttle assembly properly.

Pete the HEI units you want are called IM45 over here and are aftermarket types available at our Autozone and Midas parts suppliers. They are used on Alfa, Chev, Ford, Peugeot and Renault as per their listing.

A year or 2 back Don bought two Bosch types that had the same configuration over in Oz, but I am not sure if he got them working and think he did not try them yet.

I just recalled that I actually used 2k thinners to soften the resin/epoxy on the flasher self cancelling unit

Thanks Matchless. It looks like there's a Bosch BIM024 that's also compatible, but I think the configuration is different and it's straight as opposed to angled. I found the following compatible part numbers and details also on a Google search:

Bosch ignition module part number BIM024

these are all the same thing

KEM #E200
Standard #LX301
Motorcraft #DYG-216
Napa online ECHTP45
Wells DR100
Niehoff DR400
AC DELCO D1906
summit ACC-35361

Here is how to wire it up. The four HEI module terminals are labeled W, G, B and C.

W = positive lead (+) from the pickup
G = negative lead (-) from the pickup
C = negative side (-) of the coil
B = positive side (+) of the coil

Bolt hole through to -ve earthing on car
use large heat Sink or aluminium mount to conduct away heat quickly

Also someone who did one for a Honda:

http://webpages.charter.net/n8nxf/HEI-CX650C.pdf

Thanks for the auctions there Matchless, I have seen those ones. I'm trying to stick with local Aussie ones at the moment because when they finally fix their quantities and listings, it will only be a day or two away whereas it'll be at least 2 weeks from the US without spending a fortune on postage.

I'll have to PM Don to see if he did anything with it. He's been a little occupied with his VX800 lately

[Matchless]

Pete,
I have built the one for the GS1000 and it works quite well. I keep it as an emergency spare.
I am not sure about the Bosch one, but still have the schematic for connecting it up somewhere.
The only real issue with the HEI modules are that the signal from the pickups may need some lifting a bit. You can test with only one module if you can get your hands on one.
You will also see that Napa one listed has TP45 at the end. Mine are actually marked TP45
SuzukiDon was going to use the Bosch types.
Keep well

[pete]

Pete,
I have built the one for the GS1000 and it works quite well. I keep it as an emergency spare.
I am not sure about the Bosch one, but still have the schematic for connecting it up somewhere.
The only real issue with the HEI modules are that the signal from the pickups may need some lifting a bit. You can test with only one module if you can get your hands on one.
You will also see that Napa one listed has TP45 at the end. Mine are actually marked TP45
SuzukiDon was going to use the Bosch types.
Keep well

Cheers again Matchless! I've found a diagram on your Mediafire site for "Ignitor_Bosch_HEI_for_GS650.pdf", and that shows the straight Bosch style modules. Thanks

I PM'd Don before so I'll see what he has to say also.

In the meantime, I really just need to be patient because I think the two sellers I'm dealing with are probably car enthusiasts, so I suspect eBay is not their top priority, but a sideline to their normal business.

When you say the pickup signal may need to be lifted, I do recall seeing that in a thread somewhere now that you mention it. I'll have to do another search and find what they did again because I think that was a twin in the thread I saw with that done.

[Matchless]

Pete,
Here is a link to Lou's website. He helped me getting the one for the GS1000 working.

http://home.comcast.net/~loudgpz/GPZweb/index.html#home

There is some good stuff on there.

[pete]

Pete,
Here is a link to Lou's website. He helped me getting the one for the GS1000 working.

http://home.comcast.net/~loudgpz/GPZweb/index.html#home

There is some good stuff on there.

Nice one Matchless, definitely some good stuff on there! I'll have to go through that in some more detail later...

[pete]

Rightio, first off... I just realised tonight that one of the auctions for the HEI modules actually has a mobile number on there to ring for questions. Sheeesh I must be blind again...

Hopefully I'll get time to ring them tomorrow and ask them to list some more so I can buy a pair!

Now, the pic's of the horrid torture I've subjected the old ignitor to:



I'm sorry, but one ignitor was harmed in the taking of those photos...

I'm hoping I can at least salvage the circuit board and enough component numbers to be able to make another one, but I'll be happy with the HEI modules for now if I can get some.

So, I have cleaned up my old throttle and tacho cables, but I haven't lubed them as I'll be replacing them before the bike's done. I just need them on for the first start so I can give it some throttle and get the idle up to 2500rpm's for 15 minutes.



Throttle cable on after some fun:



I really need to do something about those carbs... ugly! Letting the rest of the engine down... even the dodgy prepared Black Velvet looks better!

And the much more straight forward tacho cable:

[pete]

So, does anyone recall this pile of toilet rolls and paper towel rolls etc?



Well I started turning them into something tonight...



I must say I'm quite happy with how that layout works.

At the moment I ended up with about 24.5 inches for the left header, and last count was 21.5 inches for the right header, but that was before adding the last length and getting them into the collector.

My aim was about 28 inches of 1.5 inch diameter for the headers and then 24 inches of 2 inch diameter after the collector, so I need to revisit that header yet.

That's it for now, so next time I'll keep going on the exhaust mock up, but hopefully tomorrow I'll be able to order some HEI modules so I can get some spark finally... that'd be grand!

[pete]

Well, called the eBay seller this morning, and they added some quantity to the auction.

So, in theory, once I pay when i get home tonight, there should be a pair of GM type HEI modules on their way to me next week.

Not celebrating until they're in my hand and generating sparks, but it's definitely a good start!

Now to gather the rest of the components and try to find a suitable heat sink...

[Woodsy]

Hey Pete,

Why does one pipe go down so low? I can only see that gathering moisture and rusting through. I would go in a similar direction to the other pipe, keeps them almost the same length and would prob make tuning easier as well?

But a good idea with dummying them up like that!

Josh

[pete]

Hey Pete,

Why does one pipe go down so low? I can only see that gathering moisture and rusting through. I would go in a similar direction to the other pipe, keeps them almost the same length and would prob make tuning easier as well?

But a good idea with dummying them up like that!

Josh

Cheers Josh! The reason i've taken it down like that is to keep both headers the same length before the collector.

As it stands right now, I think the right one is actually a few inches longer than the left one, but the left one is only 24.5 inches and I need to take it out to about 28.

The only catch with that style of header is that it won't go between the cylinders and the frame, and it has to go in front of the frame, which adds extra length to the left side header to come across to the right side.

If you look at a Triumph Scrambler with the Arrow 2 into 1 on it, you'll see what direction I'm trying to take, but how it's a little easier if you can take the pipes between the cylinders and frame:



The exhaust shop may be able to do something a bit neater and maybe there's a way they can bring it between the cylinders and frame which would be much better, but I won't know that until I take it down.

At the moment I'm just playing pre school arts and crafts really to see how it all looks...

[pete]

Ok, I'm going to use my ignitor thread to track using the GM style HEI modules and you can find it here:

http://www.thegsresources.com/_forum/showthread.php?t=171781

I'll still pop some finished pic's in here though

[pete]

Had a closer look tonight, and there is enough room for a 1 1/2 inch pipe to go between the cylinders and frame. The only question in my mind is will that cause too much extra heat that close to the cylinders? Question for the exhaust people me thinks...

However, I think going that direction will allow me not to have to drop down anywhere near the same amount on the right header, which may look a bit less odd.

Anyway, I've started to mock up a different set of headers that goes that route instead of in front of the frame. Haven't gotten far with it so no pic's yet.

[pete]

Discovered a slight issue with my exhaust idea tonight.

If I route the exhaust out the right side, then to get it in a practical position, it will obscure my access to the dip stick. That ain't a good idea!

So, while trying to think about that, I got distracted by my no spark again and ended up just sort of staring into space fiddling with the now functioning throttle...

Turns out I just can't focus on anything in the garage right now except my lack of spark, so walked out again without doing anything... frustrating!

If I get down tomorrow night, then I might see if I can get the exhaust routed down the left side.

The only thing making me hesitant about that was the choke lever, but if I'm able to do what I want and make it handlebar mounted, then that problem goes away. I think I have an idea on how to handlebar mount it that may even work too...

[Leigh]

Had a closer look tonight, and there is enough room for a 1 1/2 inch pipe to go between the cylinders and frame. The only question in my mind is will that cause too much extra heat that close to the cylinders? Question for the exhaust people me thinks...

Exhaust wrap, Pete..
Get the pipes powder/enamel coated then wrap them up.
It'll keep the heat in.
Plus it looks damn cool.
You know I'm right.

I was thinking about your two-into-one idea and was a bit doubtful but that Arrow system looks the goods.

[pete]

Exhaust wrap, Pete..
Get the pipes powder/enamel coated then wrap them up.
It'll keep the heat in.
Plus it looks damn cool.
You know I'm right.

I was thinking about your two-into-one idea and was a bit doubtful but that Arrow system looks the goods.

Aaaaah cha-ching! You're on the money this morning Leigh

My head is so into this spark thing I'm missing the obvious... exhaust wrap! And good call on the powder or enamel coating too, which would solve the potential problem of quick rusting due to moisture in the wrap.

I really wanna get it fired up so I can talk to the guys at Tranzac and see what they have to say...

And yep, I've always liked the looks of that Arrow pipe, but I don't want Tranzac to go blanket copying them either...

On a side note, I shot an email off to Slipstream Performance where I got my 'bars and rear sprocket from to check on a price for K&N filters and a front sprocket. Unfortunately the only 104 link 530 chain they have is O ring for over $100, but I have a 10% voucher for them that I'm hoping is still valid which will make the pricing all alot better...