GT550 budget build

General discussion about Street two-stroke Suzuki motorcycles.

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Coyote
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Re: GT550 budget build

Post by Coyote »

As the gecko would say ------- HELP!! I HAVE A FAT TIRE!

Those are strange looking fork tops. I don't believe I have ever seen 'squared off' ones like those. I have a standard pair of conical caps around here somewhere..You can have them if you want.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
aslsmm
On the main road
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Suzuki 2-Strokes: 73 gt 750 74 gt550

Re: GT550 budget build

Post by aslsmm »

hello, i have those covers and bolts if you still need them.
Cragdog
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Suzuki 2-Strokes: GT550L, PE250B, RM250N
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Re: GT550 budget build

Post by Cragdog »

Alright fellas, I need some direction with rear wheel spacing.
The guys at my local shop are of the opinion that my wheel is fine off center in the axle so long as the wheel is straight and the chain is straight.
It was my opinion that the front and rear wheel should be eye to eye dead center in line together.
They showed me several British bikes in their showroom that had offset rear wheels. Granted they are British bike and not janapanese. I want to get this done correctly so I'm looking for some opinions from the community here.
Currently the sprockets line up very good, but the wheel sits offset to the left on the axle.
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If you like it, then you should ride it.

1974 Suzuki GT550
1977 Suzuki PE250
1992 Suzuki RM250
1988 Yamaha YZ250
1970 Honda CB750 K0
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Suzukidave
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Re: GT550 budget build

Post by Suzukidave »

I am no expert but i follow your thinking that the wheels should be inline .
the older i get the faster i was
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Alan H
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Re: GT550 budget build

Post by Alan H »

The wheels MUST be in line or it will be difficult to lean into a corner one way and 'drop' into a corner the other way (right/left corners).
It will also scrub the tyres and handle worse than a drunk hardly ableson on a Saturday night.
If you get a board touching the back and front of the back tyre (or a length of string), it should be the same distance from the front and back of the front tyre.
Then move the board to the other side of the back wheel and repeat. The board should be the same distance away from the front wheel on both sides.
If it is further to one side but parallel, then the rear wheel is offset, if it is to one side but not parallel to the rear, then adjust with the chain adjusters.
If it isn't, as Jean Luc Pickard would have said 'Make it so.'

Clicky for piccy

More here

UK MOT wheel alignment details

The dealer will mean that some older British bikes had offset hubs, not offset wheels. This means that the hub can be slightly to one side or the other as required by chaincase/swing arm construction. Alloy wheels may have offset cast in if required, but more normally would be offset neutral.
If you look along the rear tyre as above, it will be the same line to the front wheel on both sides so both tyres run the same track.
Spoked wheels can have the offset adjusted by slackening one side spokes slightly and tightening the other side. This requires care and some experience as you can also make the rim oval if you bollox it up!
Alloy wheels can't have the offset adjusted.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
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Coyote
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Re: GT550 budget build

Post by Coyote »

If you get a board touching the back and front of the back tyre (or a length of string), it should be the same distance from the front and back of the front tyre
So that's where all the straight boards are. In the UK You might find one straight in 200 here in the USA. I use a long length of aluminum C channel. Dead straight and never bends or warps or distorts from heat or humidity. You can get the C channel at most 'upper' hardware stores. Also it weighs nearly nothing.
As far as the wheels being offset, you will never notice if both wheels are straight and the offset is slight. So the shop wasn't blowing smoke. In the real world, dead straight and dead center fore aft would be the perfect situation, but is rarely ever achieved. Also, an offset of up to 1/8 in the sprockets is OK -- as long as the sprockets are parallel to each other and not pointing in different directions.
Personally, I think you could have avoided all these headaches by using a wider swing arm off a 79-80 GS. Thinking about it, that may not work with stock exhausts. In my case I was using chambers so I made them fit what I had. You wouldn't that liberty with stockers. So scratch this idea.
I was born with nothing and still have most of it left.

.
1978 GS1000C
1976 GT550 ongoing money pit.
Cragdog
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Re: GT550 budget build

Post by Cragdog »

Good news!
I took the GT out on its maiden voyage today! :D
I ended up going back to the 16inch drum rear wheel for the time being until I can get the other 17 worked out. There is still a handful of things I need to address, but I was very happy to take her for a quick little zip up the street.

http://youtu.be/-a5SFOn_stA

Video is really short, just some clips my buddy put together for his instagram. Pretty funny though I forgot the little bolt that tightens the shifter so I lost it while getting up into second! :shock: :lol:
It was just in the middle of the road thankfully. :roll:

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Still need to get it titled and registered so that will probably be my next step now that it is very near road-ready.
Thank you everyone here for all your help and advice, you guys have been truly awesome. This site is such a good resource for these lovely machines, and the community here is filled with great people from all over.
More to come from me I'm sure! Suzuki smokers are in my blood for good. :mrgreen:
If you like it, then you should ride it.

1974 Suzuki GT550
1977 Suzuki PE250
1992 Suzuki RM250
1988 Yamaha YZ250
1970 Honda CB750 K0
Cragdog
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Re: GT550 budget build

Post by Cragdog »

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It's legal!
Spent the day yesterday at the DMV getting inspection and applying for a new title, plates and registration. The process wasn't nearly as much of a nightmare as I have heard others make it out to be for a bike that has fallen out of the DMV database. Took about 3 hours, but it's road worthy now to my delight. :mrgreen:

One thing I can't seem to wrap my head around is how incredibly noisy this unbaffled stock exhaust is?!?! :wth: It literally sounds like a race bike, and while I seriously get a kick out of her screams through the gears, my neighbors surely will have my head in a matter of weeks.. :?
How much of a difference will the baffles make? I don't really want to shut her up completely, but a little less noise when I'm coming up my street would help turn a few frowns upside down. :roll:
If you like it, then you should ride it.

1974 Suzuki GT550
1977 Suzuki PE250
1992 Suzuki RM250
1988 Yamaha YZ250
1970 Honda CB750 K0
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tz375
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Re: GT550 budget build

Post by tz375 »

Two things:

An unsilenced 2 stroke at part throttle is one of the most painfully annoying sounds around

Removing the baffles actually hurts performance,

I'd fit the stock baffles back in and if you want a little more noise remove some of the wadding around the rear section
Cragdog
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Re: GT550 budget build

Post by Cragdog »

Good call tz, the bike never came with the baffles so I'm going to have to track all 4 down at some point. Is it a relatively straightforward install or is there anything I need to watch out for? There are a couple loose pieces in the left and right pipes, but looking at the fiche for the baffles doesn't really show how they are held in place.

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If you like it, then you should ride it.

1974 Suzuki GT550
1977 Suzuki PE250
1992 Suzuki RM250
1988 Yamaha YZ250
1970 Honda CB750 K0
Cragdog
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Suzuki 2-Strokes: GT550L, PE250B, RM250N
Location: Southern California

Re: GT550 budget build

Post by Cragdog »

Looks like it could cost near $200 to replace all 4... :shock:
Are there any known aftermarket baffles that work for our GT pipes?
If you like it, then you should ride it.

1974 Suzuki GT550
1977 Suzuki PE250
1992 Suzuki RM250
1988 Yamaha YZ250
1970 Honda CB750 K0
yeadon_m
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Suzuki 2-Strokes: GT380B, GT550B, GT750A, GSX1400

Re: GT550 budget build

Post by yeadon_m »

Usually available over time on ebay - don't buy new, they are a crazy cost!

Held in place by a small screw / bolt which goes in via the cut out in the lower tailpipe and through the thin walled pipe tube then into a threaded section in the baffle end itself. Oh, and they do often self-eject so worth some wire ties until you've proven to yourself that they don't make a bid for freedom!

Mike
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Alan H
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Re: GT550 budget build

Post by Alan H »

I'm sure there are breakers with plenty of knackered silencers with decent baffles in. Make some offers.
If you get baffles that are shortened they stop the 'crack' but still sound OK.
Think of how stupid the average person is, then realise that half of them are more stupid than that.
pearljam724
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Re: GT550 budget build

Post by pearljam724 »

tz375 wrote:Two things:

An unsilenced 2 stroke at part throttle is one of the most painfully annoying sounds around

Removing the baffles actually hurts performance,

I'd fit the stock baffles back in and if you want a little more noise remove some of the wadding around the rear section
The no baffle part hurting performance. Is true and false. It will hurt performance with stock jetting. But, if it's rejetted and rejetted correctly. You should gain a few horsepower. My 550 without baffles is actually not that loud and annoying as some 2 stokes can be without. The stock pipes are so dense. It's not that big of a deal. Definitely louder, though. Like you said, you can adjust the decimal levels by pealing back the thickness of the fiberglass wrapping. You can actually tear it apart in layers. Depending how you want it to sound and still baffling some of the noise. Then, just rewire it.
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tz375
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Re: GT550 budget build

Post by tz375 »

Did you try it on a dyno with and without baffles? without baffle tubes it sounds faster but the few tests I have seen over the years suggest that performance is worse, jetted or not. When I last ran a GT on the dyno to compare pipes I didn't try it without baffles to see the result but I would be surprised if it actually improved anything.

A bigger issue for Cragdog is the fact that he mentioned something rattling around inside. That is likely to be the baffle plates that the baffle tubes go through. If you look at Ian's web site, there's a page on exhausts and somewhere there is a picture of a GT750 pipe opened up. The 550 is very similar inside.
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