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Discussion Starter #1
hi all
I have managed to get my hands on an 83' cx650c complete engine and i'm thinking of trying to put it in my gl500 frame.
am I right in thinking I will need an engine hanger from a gl650, and swap output shaft to a gl500. will the cx650c carbs be ok with gl500 frame.
will use the cx650c wiring loom.
thanks
jay
 

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you dont need to change the wiring harness the 650 will plug right into the gl500 harness they are both ti ignition motors and they both run the same stator

you will need to use the accessory fuse to provide power to the rad fan

green to ground black to switched ignition positive the 650 has a control switch to turn the fan on and off

right in the bottom of the rad
 

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The 650 carbs won't mate with the 500 airbox and the CX650C one won't fit the GL500 frame so if you want to use the original type air filter you need a GL650 or CX650E airbox.

You will also need the 650 rad because the 500 rad won't fit the 650 engine hangers plus the fan is attached to the rad and the fan switch is in the rad.

If you are planning to use an Interstate fairing the mounting holes in the fairing bracket will need to be ovaled slightly - the ones on the engine horizontally and the ones on the frame vertically. This will result in the whole fairing being raised approx.1/4" - not enough to notice.
 

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Discussion Starter #4
thanks guys.
all I have for the GL500 is frame and swingarm, and front engine mounts. will the gl500 front engine mounts work with the cx650c motor, or do I need gl650 mounts.
for the carbs, I'm hoping to use pods. is there any way I can use the cx650 carbs?
will use the cx650c wiring loom as that is all I have.
thanks
jay
 

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The studs on the 650 engine's heads are a bit higher and farther apart than the ones on the 500 so the 500 engine hangers won't fit the 650 engine without serious modification so it is a lot easier to just use 650 hangers.

You pretty much have to use the 650 carbs with the 650 engine (unless you use Murray's Carbs); As I understand it, the 500 carbs (if you had them) would work with the 650 engine except that between the 650's inlets being higher and farther apart (because of the increased cylinder size, same as the studs) and the fact that the 500 carbs are parallel but the 650s are splayed (closer at the rear), the 500 manifolds wouldn't line up with the 650 engine

There are numerous threads about using pods with the 650 carbs but IIRC, you will have to put the battery somewhere else.

If you were starting with a more or less complete GL500, using the original wiring harness would be easier but if you are starting with a stripped frame and you have the 650 harness that is the best thing to use.
 

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Discussion Starter #8
Thanks for the info chaps. Is it a ball ache to put the cx650c engine in a cx500 frame?
 

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Discussion Starter #11
Cheers. Think I'll stick with the GL frame then.
 
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No one has mentioned that you will have to change out the output shaft, which means pulling the rear cover. The output shaft on the 650C doesn't have the notch for the driveshaft bolt on it to hold the driveshaft in place. Take the output shaft from the 500 and put it in the 650. The 650C is the only twisted twin engine that lacks that notch for the driveshaft bolt.

You will want to check the cam chain at the same time, as the 650s eat cam chains faster than 500s do and you will need to replace the mechanical seal, the rear cam oil seal, the copper washer on the water pump, and the o-ring for the water pump as well as the chrome pipe o-ring, which on the 650s is not round , but tapered, and the o-rings for the water lines.I also recommend that you pull the flywheel to make sure the flywheel isn't scored where the rollers go or you might need to take it all apart again if it is scored, as your rollers catch on a scored flywheel will act up when trying to start it.

To check for scoring use a large pin or dental tool to go over where the rollers are mounted in the flywheel and if you feel anything you should put in a GL500 flywheel, as it is identical to a 650 flywheel. CX500 flywheels are different and won't work on a GL500 or any 650 motor.

If you need any good used parts, like a flywheel, go to eBay or feel free to PM me.
 

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Discussion Starter #14
thanks for info david.
does anyone know how different the gl500 frame is to the gl650 frame. want to know if I can use cosmetic parts from a gl650, ie side covers, luggage frame, saddle bags etc, and also parts like side and centre stands.
thanks
jay
 

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Discussion Starter #17
excellent thanks chaps, that makes shopping a lot easier :)
 

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Discussion Starter #18
Just picked up a gl500 swing arm linkage and monoshock for dirt cheap. Are the monoshock worth servicing or swap out for something modern.
 

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Discussion Starter #19
hi
another question: can I still use the cx650c wiring loom if I want to put on the interstate front fairing. I know the front fairing has its own loom but does that need a plug/socket on the main wiring to plug into, if that makes sense :)
atb
jay
 

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The standard (no fairing) and Interstate versions of the GL have the same main harness and the fairing harness plugs into it where the headlight, signals &c would plug in so it should plug into the C harness the same way FWIW, I have an Interstate fairing on my E and the fairing harness plugged into the E harness with no problems).

Whether to use the original shock or something newer depends on what you want to end up with. Mine is a daily driver and an original un-rebuilt shock (I did change the oil in it about 8 years ago) and it works well enough for me but a few people have changed to more easily available shocks from newer bikes with good results.
 
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