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PostPosted: Sun Nov 27, 2016 1:28 pm 
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Location: Southeast England
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Bikes owned: TS100, T200, GT250, T500, GT500, GT550, GT750, GS750
Great work Gold....good guess on the sheet thickness....we use 0.9 for mild and stainless. Mild is easy to bend, it's soft....stainless however, is a different game, particularly in the winter when our workshop is cold. We have a 120 year old Edwards sheet metal roller, which makes relatively easy work of the job, although there is still a little hand and hammer fettling required to finish.
Welding is something we have never tried too hard with....and TIG is an art with stainless....luckily we know a real good guy who does all of ours for us.

Great project, and very nice work....watching with interest.
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PostPosted: Sun Nov 27, 2016 3:32 pm 
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20 gauge is what I use too. I have a small set of rolls which makes it way easier, I'm impressed at how well you are doing without rollers. I find it doesn't matter how round you get the sections before welding because you have to dress them afterwards anyway. They are easy to dress once welded. I think my center section is 100mm dia, that probably why my pipes appear longer than yours. I think you will have your work cut out for you welding them with mig though :o I used oxy/acetylene because that's all I had at home. I have a tig now so the next set should be better! Keep up the good work I am enjoying this build :clap:


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PostPosted: Mon Nov 28, 2016 7:49 am 
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Location: Saskatchewan
Country: Canada
Bikes owned: '72 gt750
Thanks for the tips and info GoldnRust, I intend to get the Bell book before I start anything myself as well.

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PostPosted: Tue Dec 06, 2016 4:03 pm 
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Country: UK
Bikes owned: T500 RGV250
Cheer guys :) I'm glad my guesswork of 20 gauge seems to be on the money!

I'm aware MIG is not optimal really, but it's the only type of welding I can do, and I've got plenty of experience welding thin car body work panels with it, so I know what I'm letting myself in for (Pages and pages of welding on one of my old car projects here if anyone is interested in 4 wheels as well as 2. http://retrorides.proboards.com/thread/142841 ).

dgoodsy, I thought Bells book was good, certainly worth a read.

On that note, I've based my exhaust's tapers on the measurements in Bells book, choosing dimensions closer to those he would recommend for a softer motorcross/enduro style pipe, rather than a full on road race pipe. Still I'm noticing that my tapers seem pretty steep compared to lots of the other pipes on here, leaving me with a longer belly section (I think this is why my pipes look different to yours Johnu). Here's hoping I haven't let my ego talk me into making them too aggressive!

Over the past few days I've been trying to get the left hand pipe to the same state as the right hand one. From my last update you can see the cones were not far off ready, so it was just a case of tacking it together. If only it were that simple...

Image

First problem, having tacked the right hand pipe together, working out where it should run by eye, I now had the challenge of trying to match that on the left. As the cones are the same, getting it roughly right wasn't hard, but it took me a good few hours more of tweaking to get the pipe to tuck up under the pegs quite as neatly as the right. Finally this evening I've got that sorted.

Image

This leads me on to problem two... with the left pipe in this location the standard side stand doesn't fit. So I need to work out a way around this problem. :wth:


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PostPosted: Tue Dec 06, 2016 4:44 pm 
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Joined: Tue Dec 16, 2008 11:37 am
Posts: 873
Location: Trowbridge UK
Country: UK
Bikes owned: T500R, SV1000S, TS125, Seeley T500
Hi Goldnrust,

Great work, not stuff that I would attempt. However looking at the first try pipe run it looks as if you are going to run out of ground clearance with only a very moderate lean angle. It might be worth re-looking at the various T500 pipe set-up photos on the web and getting some ideas of how you can snug the pipes into the centre line of the frame. My pipes almost touch at their max diameter under the engine. A very tricky task cutting and welding a set of expansion chambers.

Cheers Geoff


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PostPosted: Tue Dec 06, 2016 4:44 pm 
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Location: Illinois
Will your gear lever and rear brake lever clear the pipes in that position, or do they need to move inboard of the frame rails?


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PostPosted: Tue Dec 06, 2016 5:19 pm 
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Bikes owned: T500 RGV250
Hi Geoff, ground clearance is something that's concerning me a little yes. Looking at the pictures I've found online, all of the pipes that run under the engine, between the two frame rails, require the removal of the centre stand mountings from the bottom of the frame, which is something I'd like to avoid if possible. I'd seen that some of the professionally made pipes, like Higgspeed and I think some of Titan Performance's pipes, ran on the stock location, so I thought that's where I'd try first. In my basic test in the garage, the right pipe grounded out at roughly the same angle as the standard foot peg (which I'm keeping) so on first impression that didn't seem too unreasonable?

Hi tz375, the brake clears fine, I need to double check the gear lever but it looks like it will.

This is my first attempt at pipes, so I'm happy to be corrected and take the criticism on board :) I've not got much money invested in them, just some time, so if they aren't gonna work I've no problem with chopping them up and going back to the drawing board.

Bearing in mind this will be a bike for the street, for going out on a nice ride on a Sunday afternoon, rather than a racer, do you guys think the ground clearance will be something that hinders me?


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PostPosted: Tue Dec 06, 2016 5:54 pm 
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Joined: Tue Dec 16, 2008 11:37 am
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Location: Trowbridge UK
Country: UK
Bikes owned: T500R, SV1000S, TS125, Seeley T500
Hi Goldnrust,

I would consider taking the centre stand out of the picture, unless you have a very specific need for one. Just use a a rear paddock stand when back in the workshop and rely on the side stand when out and about. There are always more than one way to solve a problem though, how about high level pipes?

Cheers Geoff


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PostPosted: Wed Dec 07, 2016 6:11 pm 
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Country: United States
Bikes owned: T500
Goldn, I would imagine you would have a bit of welding experience if you restored that Lancia, if I'm not mistaken they are usually riddled with tin worm :shock: Funnily enough after I get done with the Suzuki my son and I are going to build a BMW e30 for track days! I've car resto before with my dad back in the UK, a bunch of MG's and Morris Minors. Anyway keep plugging away you are doing a great job :up:


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PostPosted: Sat Dec 10, 2016 11:49 am 
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Location: Southeast England
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Bikes owned: TS100, T200, GT250, T500, GT500, GT550, GT750, GS750
It's difficult to tell from your picture, but it looks as though you have kept the pipe nice and tight to the bike. I'm guessing your widest diameter is 100mm or close?....that being the case, I would think ground clearance will be ok, unless your suspension is baggy. I have grounded the outer/lower pipe on my 500 once, but I was seriously on it, trying to prove a point.
When I was younger, the stock pipes used to touch down occasionally.

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PostPosted: Sun Dec 11, 2016 9:37 am 
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Country: UK
Bikes owned: T500 RGV250
I'm not planning on running the centre stand itself Geoff, but I just didn't want to go as far as cutting the mounts off the frame, just incase my plans change.

Johnu, oh yes when I bought the Lancia it was mostly made of filler.... :lol: About 6 months of metal work at every spare evening and weekend saw it turned around back to all metal. Not necessarily super beautiful metal work but good enough :)

Titan, yes the widest section of my 1st draft pipes was 105mm, and they were tucked in close to the frame and as high under the pegs as I dared. I figured it couldn't be much worse than the stock pipes... turns out it was!

So since the comments you guys made last week, I took a step back. I read about strapping the suspension down, to simulate a mid corner bump, then leaning the bike over and seeing what catches first. I tied the forks down some way, and fitted a bit of steel bar in place of the rear shocks, giving me what seemed about half way compressed suspension.

Image

This made quite a difference as to when the pipes grounded out. With the suspension compressed my pipes touched down with the foot peg still about 1-2" above the floor.

With the bike still strapped down, as I quick test I hooked up a stock exhaust and found it touched down at roughly the same time as the foot peg. So much better than my pipes, that's not good news.

So back to the drawing board... First things, could I just take my existing pipes and run them under the frame, regardless of the slightly ugly way they would go round the stand mounts. It's only at this point I thought to take pictures, and it was dark so they're not great, sorry.

Image

Answer.. no. They touched down with the foot peg nearly as far above the deck as they had at the side of the bike.

Some head scratching later I thought to measure the stock pipes, they are approx 95mm at their widest point. Maybe my pipes were just too fat, so what would happen if I slimmed my pipes down and ran then under the bike. A bit of card and some tape later, and I had some improvised 90mm pipes.

Image

Now we're talking, pegs are well into the floor and the pipes are still clear. I then repeated this at 95mm and they still cleared, but it was much closer. Leaving some space for mounting brackets and a bit of clearance, I'm tempted to make the pipes up at 90mm. Now I know this is now only just about 2x the port diameter, rather than the 2.2x minimum Bell suggests, but in this case it might be a lesser of two evils?

Sometimes these problems are a blessing is disguise. Going back over my pipe designs to rework them for a max diameter of 90mm, I realised that I'd made a couple of stupid errors when it came to actually drawing out my cones, so the tapers might have been a bit out anyway! I also think with a clearer head, that I'm going to go for a shallower diffuser taper, as going over the numbers again I think what I had was too aggressive for the bike really, easy to get carried away with these things.

So I better order some more metal and have a 2nd attempt!


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PostPosted: Sun Dec 11, 2016 11:46 am 
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Joined: Tue Dec 16, 2008 11:37 am
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Location: Trowbridge UK
Country: UK
Bikes owned: T500R, SV1000S, TS125, Seeley T500
Hi Goldnrust,

I admire your willingness to get stuck into tasks, and learning the skills to achieve them :up:

When making a set of pipes you are always going to have to make compromises to make them actually fit the engine/chassis + clearance etc. My pipes were made by one of the best but still have channels for the chain run and indentations to clear frame tubes etc. The pipes I had on my original Seeley T500 back in 1980 were really tucked in, to the extent that the fairing belly pan could be used, but were "compromised" from the ideal shape all over the place. They still worked very well though :D .

Keep up the good work.

Cheers Geoff


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PostPosted: Sun Dec 11, 2016 8:12 pm 
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Location: Saskatchewan
Country: Canada
Bikes owned: '72 gt750
Nice job working this stuff out, I'm sure you would rather have less ideally tuned pipes rather than pipes that bottomed out during mild corners!

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PostPosted: Sat Jun 10, 2017 5:52 am 
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Joined: Wed Aug 03, 2016 3:11 pm
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Country: UK
Bikes owned: T500 RGV250
'It can't be that long since I posted an update on my bike.... oh what, December?! Oops' That's pretty much what just went though my mind. So casting my mind back to where we left off...

Having decided that my first attempt at the exhausts were going to cause ground clearance issues, I was looking into running the pipes under the bike, and reducing the diameter of the belly section down a little. This seemed to be a good idea, but as I was continuing to work on the idea I realised that running the pipes under the bike was going to be more complex than I realised, it was going to cause some complication with the chain run and it was going to be messy and awkward to make it work with the side stand. I also took a step back and thought about how I want to use this bike and my riding ability, it will be a bike for Sunday rides on the road and I'm no racer.

With that in mind I went back to the idea of pipes running up the side of the bike, similar to the stock location. Sticking with the smaller diameter belly section I had planned to use for the under bike pipes, I found I'd picked up a good amount of ground clearance, should get the pegs down just marginally before pipes, which will be plenty far enough for me! haha.

Image
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You can also see there my home made silencers. The only silencers I could find on the shelf seemed to have quite small diameter inlets, aimed at 125cc cylinders I would presume, so I made some! Thankfully it's nice an easy in the modern world of internet and eBay to get hold of the various different diameters of tube needed and they aren't complex to make.

Now that I was happy with the design, I seam welded the pipes up properly and then dressed the welds down.

Image
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After this I got distracted for a while, by the excitement of taking my ‘modern’ (It’s only 26 years old) bike on a track day for the first time.

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With that distraction out of the way, next up was to take a deep breath and then get stuck into the T500 engine. First step was to give the cases a clean up.

Image

On the whole they looked in reasonable condition. They do show some scars from what I would guess is plenty of bits of smashed piston floating about inside the engine, but I dressed any sharp edges down and I think it’ll be fine. I also had to replace one of the locating pins for the gearbox output shaft bearing, as it looks like someone had tightened the cases down with the bearing not over the pin at some stage and mangled it.

Next up was to look at the crank. I measured the clearances and satisfied myself that all that was needed for now was to replace the seals. With that in mind I just separated the centre section, and left the big ends assembles. It came apart without too much drama.

Image

My new crank seals were going to be 3 weeks in the post from Suzuki, so in the mean time it was time to look at the top end. First up I checked the heads for flatness. Bearing in mind that the engine came to me with some stripped threads in the head bolts and a improvised head gasket made from cork gasket material, I figured the heads had not been carefully torqued in the right pattern…. Unsurprisingly the head were quite a way off flat.

I used the old sandpaper on a sheet of glass technique to get a nice clean flat surface on the heads.

Image

Onto the barrels, and once I’d helicoiled the damaged threads and given them a general clean up, it was time to look at the exhaust ports. Back in the winter before I built my pipes I’d settled on the idea that I’d like to do change the exhaust port timing. From the books I’ve read, the intake and transfer ports dimensions suggest the engine making max power around 6,500-7,000 RPM, but the exhaust port seems to be much more conservative than that. This theory seems to be matched by the specs available online for what the TR500 porting was like, where the exhaust port is lifted by a huge amount and comparatively small changes are made to the transfers and intake.

With this in mind, knowing I wasn’t going to be running a lightened/balanced crank and that I wanted a bike with not unreasonable street manners, I decided to keep my intake and transfers stock (which are tuned to 6,500-7,000 RPM) and raise the exhaust port by 3mm to bring it up to a height where it should also be tuned for around 7,000 RPM. Here it is marked out.

Image

And then ground it out. I’ve never done any 2 stroke porting before, but I have done port matching of intake manifold and some minor head porting in car engines before, so I didn’t feel too far out of my depth. I have to say, the nature of working on a 2 stroke cylinder was quite awkward compared, it much be even worse working on something with a smaller bore! Here’s a photo after I’d done the rough shaping and before I did a bit more tidying up and smoothing.

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As you can see I had accidentally caught the bore in one spot. I wasn’t too worried though, as I knew that the next step was to send the barrels off to be bored out to second oversize to remove some scoring from the previous piston damage this engine had clearly suffered.

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I’ve gone with GT750 pistons, I’d read they are lighter and stronger than the T500 pistons and also aftermarket GT750 pistons are available for very reasonable prices. When I came to assemble the engine I found one issue I’d not seen mentioned anywhere else on the internet, that is that the GT750 pistons have a wider space for the little end bearing, and the GT750 uses little end thrust washers, whereas the T500 pistons don’t use any thrust washers. I purchased some thrust washers to take the side clearance down to match the original T500 space.

It was a busy few weeks waiting for the seals and the next thing on my list was to look at the carbs, obviously with plenty of cups of coffee to help the process.

Image

Jetting wise, I’ve made the best guess I can, and will obviously have to make changes once I can get the bike out on the road. Reading around on the forum I’m seeing that for pod filters and expansion chambers there seems a general suggestion that going up from the stock 30 to a 35 pilot is probably a good move, and for the later carbs going up from the 97.5 main jet to a 115/120 main jet. As my carbs are the earlier type with a 150 main jet, I did a little calculation of the change in area of the jet and think that a 180-182.5 main jet will be roughly the same rise in flow.

Next up I gave the engine covers a quick lick of paint.

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Finally the new crank seals arrived :)

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So with the loan of a friends press for a few minutes to press the crank back together I was able to set about truing it and then assembling the bottom end and gearbox.

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Pictures are a bit scarce as, like my poor updates to this thread, it had slipped my mind as I was rushing head long towards being able to actually start the bike!

It didn’t take long to get the top end on (aside from waiting for some thrust washing in the post for a day or two) and then the oil pump and carbs on.

Image

I set the ignition timing to 3.1mm, a little less than the stock 3.4mm, bearing in mind that my engine is now in a bit higher state of tune. I’ll keep a close eye on it once I get on the road, as I’m aware my heads probably really need converting to a squish type to match the rest of my modifications. In the short term I figure I can back the ignition timing down further if needs be to keep knock at bay.

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The only thing left really was to play with the electrics. I splashed out a little and bought myself a modern digital rev counter and speedo. I like the fact that on first impressions it’s just a simple rev counter, but theres a small digital speedo in there along with the neutral, headlight and indicator lights and a volt meter.

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This resulted in many many wires to be messing with!

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It wasn’t too bad though, points and carbs, rather than fuel injection as I’ve worked with on cars, rather simplifies the wiring!

With that sorted it’s basically a complete bike! (Excuse the wiring behind the headlight in these pictures which still needed tidying up and shortening)

Image
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And so it was time to kick it over and see what happens! As usual it never goes quite a smoothly as it might seem reading one of these build threads, I had a couple of days of chasing up all those little problems which I didn’t spot previously, for example putting fuel in the tank for the first time and finding the fuel tap leaks, or spending a good few minutes kicking the bike over before realising that the plug leads are on the wrong way round… But after much swearing and grumbling at myself it fired up and ran pretty well.

https://youtu.be/Smnkc1RZ00Y

First impressions are that I’m really pleased with how its running, while it’s idling and revving ok, I’m sure there’s jetting improvements to be made, more importantly to me it sounds pretty smooth, no nasty noises from my crank rebuild or anything. The oil lines bled up fine and don’t appear to be getting any fresh bubbles in which is useful.

I took it down for an MOT, which it passed with just an advisory for the loud exhausts! haha. And I’ve sent the paperwork off to get it registered in the UK, so just waiting for that to come back and I can take it for a proper ride. :)

Prior to this the oldest bike I’ve ridden has been my old 1989 RGV250, which was still light years ahead of this in technology, so from the first short ride down to the MOT place I wasn’t sure of what expect. It was great though, considering I was keeping the engine revs low while it runs in, and only giving it a little throttle, it was shocked at how fast it seems, can’t wait to get it on the pipe and really set it free! The whole bike felt so raw and exciting to ride, I really enjoyed it. Riding at 25 MPH down some residential roads has never been so exhilarating! hahaha.


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PostPosted: Sat Jun 10, 2017 7:48 am 
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Joined: Tue Dec 16, 2008 11:37 am
Posts: 873
Location: Trowbridge UK
Country: UK
Bikes owned: T500R, SV1000S, TS125, Seeley T500
Hi Goldnrust,

Great to see you getting the engine running. My only comment is that 3.1mm BTDC for the ignition might be a bit adventurous on modern unleaded petrol. I have been running at 2.9mm on my race engine but will start with even less advance on the new race engine. Probably 2.4mm BTDC to start with and advance in small stages when on the dyno to dial it in.

Cheers Geoff


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