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Just Here For The Party
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Discussion Starter #1
Had so much fun last year, thought I'd give it another go this year. I was bouncing a few ideas around, trying to clear out a few projects taking up space and collecting dust when I got a phone call. A little back history is in order:

I was bartending a few years after college, surfing craigslist and I saw an add that said "Ninja 750, $300. Needs work." I happened to have $300 in my pocket at the time and before I knew it, there was this ravaged mass of metal in the back of my truck.



Naively I believed it would only take a few weeks to get it back together and I'd be riding all over central Ohio. Two years later, I cleaned the carbs, changed the oil, slapped a gas tank on it and fired it up for the first time.



Fast forward a few years, and I'm elbow deep into motorcycles. It's a full blown addiction by this point. I'm working at a motorcycle shop selling parts, I own a few bikes, and I've got a shed full of parts and projects. The ninja is my daily rider, and one day at work I thumb the ignition and nothing happens. No ragged purr of an old, worn inline four. No bark of an exhaust as it coughs up a few more strands of packing. Nothing.



The starter idler gear had decided to annihilate itself. The only way to replace it was to tear the motor down and split the cases. Two friends of mine had just started a motorcycle shop of their own, needed business, and I had a broken bike. Match made in heaven. They agreed to do the whole thing at cost and I let them know to not let it get in the way of more profitable work. Life happens, and suddenly it's last friday and my phone is ringing.



"I don't know if you've heard, but we had to close down. We've been trying to finish up the last few projects, but we're out of our garage and we don't want it to turn into two more years of you waiting to get your bike back. Do you still want it?"
 

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Just Here For The Party
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Discussion Starter #2
This bike has outlast more roommates and relationships than I can count. It's been a constant source of pride and frustration. Somewhere along the way it went from being a bike, to being a part of my identity. This bike is the reason I got into motorcycles in the first place. Without it, I would have never started working at a bike shop, never been to a vintage racing event or a swap meet. "Of course" was all I could say.

Last night, they bring back the bike and a few boxes of parts. The bottom end was rebuilt/refreshed and put back together. Leaving me with the top end to rebuild and my entry for the winter build off:

Phoenix Rising





I should take a moment to say that this wasn't a case of two guys flaking out and half finishing a project. They laid it on the line trying to succeed on their terms, and it almost worked. Not having the bike back meant there was still a chance, they were still pushing and fighting. When I heard they couldn't finish the project, it meant their dreams were over. It was done.

They compensated me as well, more than enough.



Normally I'm all about toughing out the cold, but when you've got prime space in a heated basement, all bets are off. It's been pulling double duty as workshop for the home remodel my fiance and I are doing and storage.



The plan is going to be straight-forward:

1. Rebuild the motor
2. Give the heads the Mototune once over
3. Better bodywork
4. 17" front and rear rims
5. Rear Suspension upgrade
6. Something special for the front end.
 

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Just Here For The Party
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Discussion Starter #3
Up early this morning, and after several rounds of coffee and the internet, got to work. There's not much that can be done until I get the pistons installed, so that became job number one.



The first cylinder looked good.



Second one looked good.



That's not so good, but useable.



That's not going to work. This was something I was aware of and had ordered a second set of cylinders to replace the first. No surprise here. This is the major reason I wanted to tear the whole motor down. I just didn't know how badly it was taken care of.



I cleaned all four up a little bit to see what I've got to work with. The flash rust on all of these made it difficult to see their condition. A little WD40 and some steel wool later left me with two, maybe three, useable liners. They're definitely going to need honed, but it's solid.



I'm waiting to hear back some information about the cylinders and rings before I install them. Additionally I'll need to polish the pistons. So I moved on to begin tackling the head. They weren't as bad as I thought, just some carbon build up.



Some of the neglect is mine, but not all of it. Maybe 5% is mine. The guy I bought it from told me the guy he bought it from was pretty rough and tumble. This bike was beat hard and put away wet.



A few hours with sandpaper and they're looking much better. I've got the whole head soaking tonight to clear up anything in the internal passages. Looking at how Kawasaki did the intakes I'm not going to be able to do much in terms of intake work. It's even to small for the flex head attachment.

 

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Just Here For The Party
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Discussion Starter #4
For the first time since I have no idea, I have to deal with the problem of paid time off. I've never had paid time off before really, but apparently it has to be used up before the end of the year. I took today off work and spent some time with my fiance, a little time outside in the garden, and a big chunk of time working on the bike.



The pistons weren't bad, all things considered. I just gave them a little love, made sure to smooth any high spots, deburr everything, and round off any sharp edges. They're in better condition than I thought, but not great condition.



I maybe spent an hour total on all four cylinders, but you can see the difference from the start (on the right) to the finished product (on the left). I'm getting lucky so far, because the few sets of rings I've seen available have a high enough price tag to cause a bit of sticker shock. Although I did find out there is a .50 overbore available.



Most likely this is overkill, but I mean come on, look at how shiny it is!

While I was looking for parts on ebay, I found a mostly complete ZX750F motor for a decent price. Sent a few questions to the seller, and a couple rounds of negotiations later I bought it. If the rebuild fails or something happens during the shakedowns, I've got a spare motor to use. It also lets me put a motor in the bike to use for mock up work on things like headers, frame or suspension mods. Worst case scenario is I rob it for parts and then sell the rest and break even.

I also caught a rumor that Kawasaki had released a race prep book for this motor. This was the power plant for their ZRX-7 race bikes, so it makes sense that they would have provided this information to their factory supported teams.. I tracked down a few teams who actually raced the GPX/750R at Suzuka in 88, but information is surprisingly limited. Surprisingly, two of the companies are still around. I sent some emails earlier today but if anyone has some leads on this, PM me or hit me up in the discussion thread!
 

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Just Here For The Party
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Discussion Starter #5
I was going back and forth on doing the heads just based on how long the intake runners are, and how difficult it would be. While waiting for parts to come in, I had time to think and read. I came to the conclusion that the worst thing that could happen would be I ruin a head.

I found an older style flexible head attachment for the dremel. It's slimmer than the one offered now and I need all the reach I can get. Once it came in, I got to work!



Before the madness begins!



And after!

A friend of mine races lawnmowers, and is a genius when it comes to engine work. He swears by dimpled intake ports, and from what I've read on the matter it makes sense. I'm going to go one step further and go for high velocity ports, at which point the dimples will help the epoxy hold better. However if that fails, then I'll run with just the dimples.



For those wondering, I'm following this guide specifically, issues 18-21. I might not be able to do the exhaust ports due to a lack of aluminum welding ability at the moment. The website is a little dated in its look, I apologize.
 

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Just Here For The Party
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Discussion Starter #6
Got some time today and dove off the deep end with the head work. Spent some quality time in the basement with the dremel and finished the last little bits of prep work on the intakes.







It took some work but I dimpled almost every square inch of intake surface. Spent a little time with a wire brush in the dremel and cleaned up all the surfaces, then I soaked the head before washing it with soap and hot water. In preparation for the madness.



First thing is that the valve seats need protected. Nothing like a little color.



Like I said; the deep end. It lacks the smooth finesse that I would have liked, but my hands were shaking and I couldn't get the JB Weld to behave quite as well as I would have liked. Still, when I was done with the fourth intake everything had smoothed out and didn't look half bad.



I'll let it setup for the night and probably all of tomorrow as well.


Money spent: $35.00 on JB Weld.
 

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Just Here For The Party
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Discussion Starter #7
Halfway through sizing and smoothing the JB Weld, the collar on my flex-attachment decided to give out! Which was somewhat fortuitous as a windstorm knocked down the privacy fence between my home and the neighbors driveway. I had to take the last few weekends to design and build a new privacy fence.

However, parts and tools have been rolling in! I was out at Lowe's today and saw they had a deal on their 300-piece toolkit. It ended up being more than a deal! The whole thing was discounted down to $103.20!?!?



And the family came together and gave me a down payment for a tig welder:


I've wanted a TIG for quite a bit of time and I've been doing my homework. I've only got 110v in my garage, and we're not planning on staying here for long enough to justify running 220v out. So I needed at least 110v, but the 220v option on the Alpha was a nice extra. I wanted to be able to do aluminum as well, so I needed the ACDC option as well. The majority of reviews all agree it's a surprisingly good welder for the price, and the only complaints I've seen have been shipping problems.

So we'll see how terrible I am at TIG welding before too much longer!
 

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Just Here For The Party
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Discussion Starter #8
The right tools make the job so much easier. For years I was always trying to cheap and jury-rig my way through things, it just added so much unnecessary frustration and stress. That being said, there's always a place for homemade tools and I firmly believe there are easier/simpler/cheaper ways of doing things than what people will tell you, but nothing beats having the right tool for the job.




The intakes have been shrunk down to about 30% their original size and the rough shaping is finished. I'll go in tomorrow and hand shape the rest. After that, the head is going off to be ultrasonically cleaned. I figure that will not only get all the dust out of every internal passage, but the heating and cleaning cycles will be a good stress test for the JB Weld. If it breaks and flakes off during cleaning, I'm only out a head. As opposed to being out an engine.

The before shot:

 

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Just Here For The Party
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Discussion Starter #9
Had the day off from work, and focused on the hardest part of the build thus far: putting the cylinder block on to the pistons...





Yes, yes. I know, it's easy. Simple! Any idiot with half a brain can do it! The last time I tried to do this, I ended up cracking the piston skirt. With that sterling success under my belt, I set about not repeating the mistakes I made previously.



The pistons are lubed with assembly grease, the rings are gapped, and everything is ready. I already installed one set of piston circlips and after watching a ton of youtube videos with guys struggling and working way to hard; I thought I'd share what I found to work really well.



Install the open end first! Don't mess around with doing one side or the other and possibly scratching the piston. Slide the open end into the groove and then use one thumb to hold them in place, while your other thumb gently pushes the top of the clip down and in. The sharp edges are held in place by the groove, so only the smooth rounded part of the clip contacts the piston. Sorry I don't have pics of the whole process.



The pistons are ready, and after smearing assembly lube over the freshly honed cylinder walls, they're ready to go. I scored an awesome deal on a set of pistons and a cylinder block along with some other spare parts on ebay. The block and pistons only cost me $35! Woohoo!



I saw one video where a guy used pipe clamps and then cut pieces of milk carton as DIY piston ring clamps. I didn't have a milk carton but I did have an empty Maxwell House coffee can. It worked beautifully!



Some light pressure and a bit of wiggling, resulted in the block sliding over the pistons! I did it. And then I realized I forgot to install the intake side cam chain guide. Which is held in place by an axle and a wedge in the crankcase, and that assembly is held in place by the block.:oops:

After fixing that and sliding the block back into place, I then realized that the axle and wedge were supposed to go inside the loop made the cam chain.... :doh:

Just look at the obligatory art shot and snicker quietly behind my back please.




COST: $70.00
 

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Just Here For The Party
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Discussion Starter #10
Currently waiting to get the valves and rockers back from my friends. They were overlooked in the exchange and left on a workbench in their garage. I thought today, I'd dig the frame out of the garage and start prepping it for bracing.

After digging out the garage door from the snow, I find there's currently a half inch of ice along the floor of the garage due to all the snow melting. Everything is frozen solid to the ground. Woohoo
 

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Just Here For The Party
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Discussion Starter #11
I'm waiting on the valves to come in, but with March almost to an end, the work must move forward. Part of the idea behind this build is to take almost every aspect of the bike and improve it, with the engine in a holding pattern, I wanted to tackle the frame. I started looking around for information on frame bracing. I first found Arnouts GSX1100.com site with a really good write up on bracing the GSX1100 frame. It's similar enough to the ZX750F that it would be useful. I kept looking a little bit more and stumbled on an article by Tony Foale about stiffing the Kawasaki 750. I figured it was going to be the KZ750, but it would be worth a good read anyways. I was wrong! It was dealing with MY BIKE!!!





Hit up Lowes and Tractor Supply yesterday and got everything I needed to brace the frame. Spent most of yesterday cleaning the work area and disassembling the roller. This morning marked the beginning of the work! I apologize in advance for the small photos. My camera was dead, and I didn't realize until I downloaded them that my phone decided to use a smaller resolution than I set it for... Not cool.



The patient is ready. Following the pictures from the article I started grinding the paint off the areas to be welded. Got it all down to shiny, bare metal and started measuring the lengths needed for the braces. I was originally going to start with the gussets that run along the bottom rails but realized that was going to be a complicated piece to cut. Plus I've never really done round tubing before and I was excited to try it. I started with the braces for the section above the swing arm. It's pretty stout and relatively hidden from view. Any learning mistakes will be hard to spot and relatively harmless.



A piece of wood with an angle notch makes for a great clamp for tubing. This setup let me use both hands to hold the grinder straight and level. After cutting the piece to length, I marked where I'd need to cut the angles to fit it into place. After those cuts were made, I swapped out the cut-off wheel for a flap-disc and shaped the tubing to fit.



First test fit for the upper piece. Not to bad, but could be better. More shaping. I'm going in a different route than the article. I'll be remaking the subframe, relocating the battery, and running a different intake setup than stock. No need for the pyramid, I can run a straight X.



Better. But not quite where I'd like it to be. Back to the flapdisc!



There it is! I did the same with the bottom and was able to tack it into place with my new welder (which once I figured out how to use properly works SPECTACULARLY!). Just as I started to get a good groove going with actually burning it in, it promptly ran out of welding gas.

$100 on sheet steel and tubing.

Total Cost: $170.00
 

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Just Here For The Party
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Discussion Starter #12
I upgraded to LED bulbs in the basement. It makes a huge difference. Same settings on the camera, only thing different is the bulb.

Before:


And After:


These are the cheap LEDs from Home Depot. The $5 and $6 bulbs available from Lowes are much better in quality and light output. Even still, huge difference in visibility!
 

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Just Here For The Party
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Discussion Starter #13
I really got down to business with the new welder last week. I am a complete novice with tig welding, so take my review as just that. WIth that said though, I've got nothing but good things to say about the AHP welder, especially considering its price. It's no Miller or Lincoln, but if you want an AC/DC tig welder it's perfect. A few upgrades make it a great machine to use, especially the addition of a flowmeter. And that's the other great thing about it, the upgrades aren't machine specific. When the time comes to move up the food chain on tig welders, everything bought for the AHP moves with.

I started messing around with settings and youtube videos, but I wasn't really improving the way I wanted. The Columbus Idea Foundry offers private TIG welding lessons. I had looked around at other options, but the local community college wanted me to go through the cycle of stick/OA, MIG and then TIG and the closest TIG class was offered by Hobart in Dayton. Not really looking to drop a thousand bucks or a year of my time, so a few emails later and I met up with Todd and we got down to welding.



In terms of jumping the curve, a welding class is a great investment. Having immediate feedback on what you did right, wrong, or should try means improvement comes on the very next weld. The above photo was my second TIG weld of the class, and three hours later I was laying a weld like this:



I still need practice (obviously) as I don't have the consistent touch yet, but that's going to come from more and more welding. I probably would have gotten to this point, but it would have been days of fiddling and tweaking and extra materials. Feeling confident with my ugly, yet solid, TIG welds. I got to work on the frame bracing.



I started with the rear most brace and got that cut, fit and welded in. I'm probably putting too much heat into everything, but that's probably the lesser of two evils. I'll be checking all the braces regularly when I start riding again to make sure no cracks develop.



Moving the torch around the tube still needs some work. Part of me really misses the ease of MIG, but that's quickly overruled by the 3-4 seconds of perfect TIG welding I periodically get. The precision with TIG is incredible!



With the rear X braced in, I started cutting and fitting the front brace. The first piece in was the top cross tube, which was welded in fully. The braces will only be tacked into place until I can test fit the motor and make sure there's no interference with the exhaust pipes. I made one change from what Foale did on his bracing. He tied his angle bracing in below the upper cross tube. I decided to tie it all in as a node.

I've got the day off work, hopefully I can get more done today and move on to the next part of the build!
 

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Just Here For The Party
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Discussion Starter #14


It's not permanent, but I slapped the head onto the motor and installed the whole thing in the frame to see if there was any interference with the exhaust system. The front bracing might interfere slightly but it doesn't look like anything major.



Fueled up and ready to go! I don't have a tube notcher (yet) so I've been doing all the cutting and fitting by hand. With that said though, there are easier ways to get closer to a perfect fit. It's going to take a few hours to really cut and fit tubing, so any shortcut is a good thing. This is that moment where trigonometry/geometry could save your life, it's all angles, triangles and math for a little bit.



I took the necessary measurements (diameters of the tubes involved, angles, tube wall thickness) and punched them into TubeMiter. It generated and printed a template that is transferred over to the tube to be cut. Simply cut and grind until you get a match.



It only does a single joint, but still it saves a tremendous amount of time in the actual shaping and fitting. For the upper corners, I wanted the pieces to tie together for strength, so I just slowly ground down a curve until it fit.



After I was happy with the fit, I used the dirty thumb method of template making and had an easy way to make an identical fitting piece for the other corner.



After I installed the motor, I held one of the braces in place to check for any issues with the headers. I used a piece of PVC pipe, and while there's going to be some issue, I don't think it's anything worth stopping for. Plus, if it does come up, I've got an excuse to make a custom exhaust!



On with the welding, then! Slowly getting better at this TIG welding game. Emphasis on the slowly. Like I said, I'll be watching all of these welds closely after I start riding.

 

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Just Here For The Party
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Discussion Starter #15
Made the delightful "mistake" of dropping in on NeverEnough while he was racing XR100s today... I now need an XR100, because what's one more motorcycle at this point. This would also be why I didn't do any work today as well. :jpshakehead.sml:





 

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Just Here For The Party
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Discussion Starter #16
So this happened today:





In hindsight, it would have been easier to have made a new shock mount from scratch as opposed to mixing and matching pieces together. Live and learn, but the results are great.

It even worked with the stock pivots, after a little filing.



With the frame welding "officially" done, I was able to move it outside and throw the wheels back on. With those on, I began working on the new gas tank and tail. The original plan was to do all sorts of crazy momo stuff to compliment the motor, but with 21 days or so, an alternative front end wasn't in the cards. So I'll focus all my efforts on new bodywork.



I made a simple jig to let me draw a profile and then build off of that. After I cut the profile out, I started into a little CAD, Bad Obsession Motorsports style: Cardboard aided design!



After much cutting and taping, I ended up with one half of a motorcycle tank and tail.



It needs some tweaking, but it's in the right direction. Tomorrow I'll flatten it and transfer it over to aluminum and begin bending it up.



I never got over doodling, I still do it even while I'm at work. I think it came out pretty close to the original sketch, minus the front end.



As an aside, Dewalt's impact-resistant goggles are amazing!

Total Cost: $220.00
 

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Discussion Starter #17
Turns out, I have the wrong welding gas to weld aluminum (much thanks to Shinyribs and Rubbersdown for their help on sorting this out). I've got feelers out right now trying to source a tank of argon, I'd really love to have all aluminum body work, but until that becomes a reality I present PLAN B!!!





One BMW gas tank, bought on eBay a few years ago because it looked cool. Never had gas in it, and had a major dent on the right side. I think I paid $20 for it. The bottom has been removed.



The bottom of the gas tank that was on the bike. It fits over the tunnel and pretty much bolts right up to the frame. Prior to doing this, I washed the tank with soapy water and then flushed it for five full minutes.



First fit looks promising. A little work and some trimming and I'll be alright I think.



Total Cost: $250
 

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Discussion Starter #18
Bad News... I'm out of welding gas. Unfortunately I bought it from Tractor Supply Co, and I can't easily exchange it for a cylinder of argon. Plus, it's technically the wrong gas for TIG welding, so there's no point in me getting a refill.

That also means that I'm out in terms of finishing this bike. I'll still get the engine together by the end of the build-off so I've got that going for me.

It's good and bad, I was grooving on the plan b tank lines, but I really wanted to finish the original tank and tail.

Lessons learned (more for me to get it down, feel free not to read):

1. Go big with the ideas, and scale down to a more restrained approach. There's always time to do the extra things at the end.

2. Project management is time management. Come up with a good, reasonable schedule and then stick to it.

3. Set a tight deadline, even if there's no reason too. Getting done early means more time to enjoy the finished product.
 
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