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Discussion Starter · #1 ·
I'm restarting my build thread for the AdvWing, copying the relevant content from the old forum:





Randall-in-Mpls' date='11 May 2010 - 05:45 PM said:
I came home this morning with about half of a GL500 basket case to start my dual-sport project. I chose the GL because the pro-link rear suspension is used on many Honda dirt bikes, and I'm hoping that substituting a dirt bike shock will give me the higher stance and greater travel that I want.



I've got a frame, seats, engine, rear wheel, and full electrical harness. This was a parts bike that had been crashed, so there's no front end, tank, or body work. The seller used the engine for a transplant a couple years ago. Between this and the CX lump I got last month, I should be able to build a runner.



The frame is a little tweaked, so the first task after stripping it down will be to straighten it (advice, please?), or have it straightened. If that's successful, I'll pursue a salvage title.



Next, I'll mock up a rear shock (he had already sold the original, but I wasn't planning to use it anyway) to measure the amount of travel that the drive shaft u-joint will tolerate. Then, hopefully, I can identity a shock with the right specs.



-----------------------------------------------



Beyond that:



Front end from the triples down - I have the original (broken) triple, so I can do a stem swap if I need to. The seller offered a good price on an '89 YZ125 front. Would that work?



Handle bars - something from a dirt bike. Shouldn't be too difficult.



Fuel tank - plastic, maybe?



Body work - I might try to mount some dirt bike plastics. If I use a stock GL tank, some of the CR side panels look like they might mesh with a little modification.



Side stand - will need to be longer, and with a larger pad. Maybe a stock stand from something else will work?



Seat - I'll most likely set up for solo using the stock seat pan, and build a box on the back. I should allow for the 2-up option, though.



Spoke rear wheel - I'd use the "German method" that's been posted, with the GL hub and a donor rim.



Exhaust - I'd like to get the H-box out from under the engine to increase ground clearance. Maybe do divorced resonance chambers with a later crossover, or into a shared can. Or a custom dual-inlet resonance chamber with a single outlet. I haven't thought this out too far yet.



Engine guards and skid plate - will greatly depend on what form the exhaust takes.



Instruments - a digital dashboard of some variety. By the time I get to this point, they'll probabaly have integrated GPS.



Panniers and other "adventure bike" extras.



-----------------------------------------------



I'll update this as I make progress, but this will be a multi-year project, so don't expect too much too fast. I'd appreciate comments and ideas, and solutions from those a little further along in similar projects.



R
 

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Discussion Starter · #2 ·
SpaceTiger' date='11 May 2010 - 08:09 PM said:
We will all follow with interest.



Two suggestions; one comment.



Suggestions:

1. Investigate increasing the rear suspension travel.. I think the stock travel distance is quite small compared to dirt bikes. The CX may have more travel than the GL model + the CX is lighter than the GL model. Not saying you should switch, but I think worth the investigation time if you are going to do some off-road time. You will want the bike as like as possible + increased suspension travel.

2. Consider efforts to lighten the weight of the frame, especially if this bike will be a single seater.



Comment: Work hard to find a plastic gas tank. The GL tank is 4.6 gal (or so) + is made of metal. A plastic tank will be lighter, hold only about 2-3 gal saving 12-18 lbs.



Jerry
 

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Discussion Starter · #3 ·
jwnovaman' date='11 May 2010 - 08:15 PM said:
sounds like a good project. If we were closer I have a GL frame without a tittle in my back yard thats strait. I would gladly donate it to you but the shipping would a large cost. I will fallow this thread for sure even if it takes a few years :)
 

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Discussion Starter · #4 ·
Randall-in-Mpls' date='11 May 2010 - 09:39 PM said:
Thanks for the comments, Jerry.



[quote name='SpaceTiger']

Investigate increasing the rear suspension travel.. I think the stock travel distance is quite small compared to dirt bikes.


That's why I plan to mock up a shock to measure how much travel there can be before the u-joint binds. That will be the same limitation as on the CX. But with the right shock on the pro-link, I think I'll get more travel than the CX shocks would allow.



SpaceTiger said:
Work hard to find a plastic gas tank. The GL tank is 4.6 gal (or so) + is made of metal. A plastic tank will be lighter, hold only about 2-3 gal saving 12-18 lbs.


My goal is to build an adventure bike, rather than a true dirt bike. I'll want a large tank for decent range. I've even wondered if I couldn't cast a form from a stock GL tank, and construct a duplicate from ABS. Just a pipe dream at this point. Haven't really looked into it.



R

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Discussion Starter · #5 ·
Randall-in-Mpls' date='11 May 2010 - 09:46 PM said:
[quote name='jwnovaman']

If we were closer I have a GL frame without a tittle in my back yard thats strait. I would gladly donate it to you but the shipping would a large cost.


Thanks. If I can't un-tweak this one, maybe I'll pursue that possibility.



R

[/quote]
 

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Discussion Starter · #6 ·
mnd' date='11 May 2010 - 10:19 PM said:
[quote name='Randall-in-Mpls']

Exhaust - I'd like to get the H-box out from under the engine to increase ground clearance. Maybe do divorced resonance chambers with a later crossover, or into a shared can. Or a custom dual-inlet resonance chamber with a single outlet. I haven't thought this out too far yet.


Scrambler style pipes would work well. Would keep the exhaust above the water line when you hit any water crossings.



Make sure you add a vent line to the final drive and the crankcase, after sealing the vent at the rear of the engine under the pulser plate. While you're there, make sure the the rubber grommets for the engine wiring are in good shape.

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Discussion Starter · #7 ·
Randall-in-Mpls' date='11 May 2010 - 10:50 PM said:
[quote name='mnd']

Scrambler style pipes would work well. Would keep the exhaust above the water line when you hit any water crossings.


I've been looking at those, too.



Make sure you add a vent line to the final drive and the crankcase, after sealing the vent at the rear of the engine under the pulser plate. While you're there, make sure the the rubber grommets for the engine wiring are in good shape.


Good idea. Missing that could really ruin an otherwise good outing..



Thanks,



R

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Discussion Starter · #8 ·
I missed a great deal on a GL500I yesterday that would have moved this project along significantly. I had arranged to go look at it after work, with money in my pocket, and some f&^@!%g breaker from Wisconsin bought it out from under me. I had resolved to buy it, but I hadn't committed without seeing it first hand.



Aside from being weathered, it was titled and complete. From his description, I suspect it just needed the tank and carbs cleaned. Plus, in the photos, I could see a Markland trunk relocator and driver footboards with relocated controls that might have paid for my whole project. I had planned to try mounting the bags (and maybe the trunk) on my CX, and sell off the rest of the bodywork.



[rant] Damn, I hate breakers! They're like the people who shoot elephants for their tusks and leave the carcass to rot in the field! [/rant]



OK, so back to plan A: straighten the frame I have and get a salvage title.



R
 

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Discussion Starter · #9 ·
Being PO'ed last night, I needed to go out to the garage and disassemble something.



I've now got the heads and rear cover off the GL engine. David was concerned about the bearings, given the foul-smelling latte I found under the valve covers, but with the front cover missing, there wasn't much contaminated oil in the engine.



Amazingly, I can see no damage from a slapping camchain. I'll know more after the flywheel comes off. There's almost all the adjustment range remaining, too, so I suspect the chain had been replaced not too long before the failure. But to show no damage, it must have been regularly adjusted by the original owner, even if it's a low-mileage engine. Everything inside the case looks clean, which is especially surprising given that someone had smeared JB Weld on the engine case joint to patch a leaking rear cover gasket, and the camshaft oil seal either wasn't replaced or replaced and screwed up.



That oil seal was so bad, the leakage was bidirectional. I found as much oil in the coolant passages as there was water in the sludge in the sump. The PO said it was a head gasket failure, but they looked pretty good. I think all the leakage was from this bad seal.



The stator looks original, but I haven't put a meter on it yet.



I'll try to get some pics this weekend.



R
 

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Discussion Starter · #11 ·
Email sent.



Thanks,



R
 

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Discussion Starter · #14 ·
Thanks for the pics, Malcolm.



















I've seen all of these before. Do you know any of the builders?



This one I like quite a bit:







Close to the level of finish I'd like to end up with.



R
 

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Discussion Starter · #16 ·
I hadn't seen that one. Nice!



R
 

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Discussion Starter · #17 ·
Finally, pics, as promised.



Here's the stripped frame, clamped in my vise, waiting for the mocked-up shock to measure suspension travel:







Yes, my garage is a pit.




I needed to reassemble the shattered clutch in order to lockup the engine with a gear:







This engine was the original from a rider owned by the PO. He bought it from an auto shop in Wisconsin, along with a crashed parts bike (the one I'm rebuilding.) When he discovered froth in the oil, he swapped engines, using his intact clutch and front cover. I got the shattered one:







The oil filter cover is a little marred, but serviceable. I'll use the clutch from my CX parts engine, and David-in-Wisconsin donated a replacement front cover. Thanks, David!



Aside from a little sooty residue, the cylinders look good:









I didn't find any evidence of the "leaking head gaskets." I think it was really the camshaft oil seal.



The cam and followers appear to be in good shape, too:



 

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Discussion Starter · #18 ·
Under the rear cover, the stator looks OK, but I have yet to check resistances:







There's a little blistering in the epoxy on the flywheel, but I don't think that's unusual (Someone, tell me if this should concern me):







Under the flywheel, the chain looks great:







I think it was replaced not long before the cooling system failure. Here you can see how much adjustment range is left on the tensioner.







You can also see where the hack mechanic at the auto shop misaligned the rear cover gasket, then filled the gap with JB Weld spread on the outside. This would be the same idiot who trashed this engine by failing to replace the mech seal and oil seal when he replaced the timing chain.



There's just the smallest amount of chain wear on the engine case. This bike was well cared for by the original owner:







So, should I stop here? Or do you think I should strip it all the way down to check the big end shells (there's no bronze in the screen or sump), replace the rings, etc.? I'm tempted to, just so I can get a good coat of moly grease on all the wearing surfaces.



Thoughts?



Thanks,



R
 

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randall,



as far as I know the hybrid cx's are from germany mainly,but isn't that one flying through the air in the USA?. there was a green one kicking around in australia that a guy from victoria had modified,dont seem to have the picture, but he does not go on the oz site anymore,like a few others I know. He was covering heaps of miles in the bush and reckons it was honda's miss not producing one.
 
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