78 GS400 special
- Thread starter Gram
- Start date
Big Rich said:
I fell lucky with that. I thought I would have to adjust the wheel to fit but the sprocket spacing is exactly the same on both the GS and XT wheels. I haven't thought too much about the calliper/ disc spacing yet but the chain will run true.
One of the reasons I chose the XT125 wheels is that they are not excessively wide to cause the chain to foul the tyre so no need to space the drive sprocket.
I'm just waiting for some 17mm bearings to match the XL600 axle, then I can make up some spacers for the rear wheel. Both the XT wheels are 15mm.
I managed to nick an hour today. The rear wheel is in but I need to get hold of a rear calliper and refit the engine before I make up the spacers.
The new engine looks ok and turns freely so fingers crossed it'll be a good one.
The ZZR yokes are set back further than the GS yokes so the forks hit the tank. The bearings are quite close in size so it looks like the spindle should need just a small modification to fit the head stock.
The new engine looks ok and turns freely so fingers crossed it'll be a good one.
The ZZR yokes are set back further than the GS yokes so the forks hit the tank. The bearings are quite close in size so it looks like the spindle should need just a small modification to fit the head stock.
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The carbs are rusted solid so I've soaked them in penetrating fluid. They should be salvageable if I can get them apart without breaking anything.
I need to make a new front axle as the ZZR one is 20mm and the XT wheel is 15mm. I thought about modifying the wheel but I would like to use the GS mechanical speedometer drive if I can.
I picked up a ZZR front calliper for 99 pence which will do for mocking up. The plan is to run a single disc and de-tab the right hand fork.
I need to make a new front axle as the ZZR one is 20mm and the XT wheel is 15mm. I thought about modifying the wheel but I would like to use the GS mechanical speedometer drive if I can.
I picked up a ZZR front calliper for 99 pence which will do for mocking up. The plan is to run a single disc and de-tab the right hand fork.
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I got the carbs split and everything freed up tonight.
Everything looks ok apart from needing a good clean.
It looks like the carbs have been apart before as most of the screws are a bit mangled. Also, I had to use an impact driver to get a couple of the free. I have a big box of stainless screws I got a few years ago so I'll replace what I can.
Everything looks ok apart from needing a good clean.
It looks like the carbs have been apart before as most of the screws are a bit mangled. Also, I had to use an impact driver to get a couple of the free. I have a big box of stainless screws I got a few years ago so I'll replace what I can.
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I mocked up the forks and front wheel tonight just to see how everything looks. Ignore that the fork legs are on back to front.
I'm not sure if to use the tail piece or not. I quite like the tracker look.
I'm going to drop the yokes and the front axle in to be modified tomorrow so I should be able to fit the forks properly next week.
I'm not sure if to use the tail piece or not. I quite like the tracker look.
I'm going to drop the yokes and the front axle in to be modified tomorrow so I should be able to fit the forks properly next week.
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Edwards engineering in Perth but any machine shop should do it. I had a few bits done at the same time so I'm not sure how much the stem cost but I would guess no more than 1.5 hours. At whatever the hourly rate is.
The stem is actually the original ZZR stem. I had the shop press it out of the bottom yoke, reduce the bottom bearing seat diameter and shorten the overall length.
The ZZR bottom bearing ID is 28mm and the GS400 is 27mm. The top bearings have the same ID on both bikes but the stem is a wee bit long. The top bearing seat shoulder is the same on both stems so this was the datum point for shortening.
The ZZR bottom seal fits the GS frame and I'll use standard GS400 taper roller bearings top and bottom. I think the top GS seal will fit as the GS locknut fits the ZZR stem but the original gs seal shattered when i removed the forks so I'm waiting for a new one to see.
If that makes sense?
The stem is actually the original ZZR stem. I had the shop press it out of the bottom yoke, reduce the bottom bearing seat diameter and shorten the overall length.
The ZZR bottom bearing ID is 28mm and the GS400 is 27mm. The top bearings have the same ID on both bikes but the stem is a wee bit long. The top bearing seat shoulder is the same on both stems so this was the datum point for shortening.
The ZZR bottom seal fits the GS frame and I'll use standard GS400 taper roller bearings top and bottom. I think the top GS seal will fit as the GS locknut fits the ZZR stem but the original gs seal shattered when i removed the forks so I'm waiting for a new one to see.
If that makes sense?
Ha... It might be an improvement..
Had a bit of a setback in that the axle I had made doesn't fit so I'm having another done today. The shop agreed to do if FOC but the machinist looked pretty pissed off. Ah well, these things happen. He'd cut the bearing seats to a 15mm clearance rather than 15mm dead so the bearings were too loose.
Would be good to get it back today so that I can fit it all together and get an idea of how everything looks. I don't want to start any frame repairs until I know what mods need done.
I want to get the frame away to the powder coaters in a couple of weeks. I'm not sure about colours yet but I'm definitely not stuck on a black frame.
Had a bit of a setback in that the axle I had made doesn't fit so I'm having another done today. The shop agreed to do if FOC but the machinist looked pretty pissed off. Ah well, these things happen. He'd cut the bearing seats to a 15mm clearance rather than 15mm dead so the bearings were too loose.
Would be good to get it back today so that I can fit it all together and get an idea of how everything looks. I don't want to start any frame repairs until I know what mods need done.
I want to get the frame away to the powder coaters in a couple of weeks. I'm not sure about colours yet but I'm definitely not stuck on a black frame.
Just after the last post the shop rang to say the axle was ready to collect.
So...here it is in its basic form.
I'm still in 2 minds about the tail piece and I'm not keen on the bars but as it stands it only weighs about 40kgs so it will end up quite light.
So...here it is in its basic form.
I'm still in 2 minds about the tail piece and I'm not keen on the bars but as it stands it only weighs about 40kgs so it will end up quite light.
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I fancy a Charcoal Black grey colour for next build.
One thing to bear in mind is that any off the wall colour tends to be expensive, most only stock a narrow range of colours and will want to charge you extra as they have to buy in the colour you want. I was quoted £25 per kilo min order 10 kilos by tripleS for a non standard colour. I ended up going to a non motorcycle specific coater who took two goes to get it right but only charged me £110 and I could of picked any colour off the RAL chart.
Have you decided on a colour for the tank and wheels?
Alternatively you could buy a powder from somewhere like below and ask your coater if they would apply it.
http://www.electrostaticmagic.co.uk/pages/powders
I particularly like the satin sand colour
One thing to bear in mind is that any off the wall colour tends to be expensive, most only stock a narrow range of colours and will want to charge you extra as they have to buy in the colour you want. I was quoted £25 per kilo min order 10 kilos by tripleS for a non standard colour. I ended up going to a non motorcycle specific coater who took two goes to get it right but only charged me £110 and I could of picked any colour off the RAL chart.
Have you decided on a colour for the tank and wheels?
Alternatively you could buy a powder from somewhere like below and ask your coater if they would apply it.
http://www.electrostaticmagic.co.uk/pages/powders
I particularly like the satin sand colour
Weldangrind
Quae nocent, docent
I appreciate how the line of the cowl matches the frame angle. Subscribed.