My T500 cafe

[ja-moo]

Mild or SS is ok, they just have to be rubber mounted.

[ConnerVT]

Is there any downside to using the early model carb holders? I figured they must have changed those out for the longer ones in 1971 for a reason.

There is no downside to the shorter intake tracts. Suzuki changed the intake tract lengths in 1973 to detune the engine. The performance of the GT550 introduced in 1972 was no better than the T500, presumably Suzuki decided to detune the T500 to make the GT550 more attractive. Jetting and carburetors were also changed, the 1972 and earlier models used #150 round main jets, whereas the 1973 and later used #97.5 hex main jets. Since your running chambers and pod filters with ported cylinders, you'll need to spend time sorting out the jetting.

Let me add some more input into this. I agree with most of what desmocat wrote, but what I understand is a little different.

The main difference between the early and late carbs is that the early carbs were homo-pressure body, and the later (1973 and newer) carbs were vented normally. Suzuki experimented with what they called "Homo-pressure" carbs, where the fuel bowl was vented to the carb's intake bell, rather than to outside atmosphere. The change necessitated a change in jetting (#150 ROUND to #97.5 ROUND, not hex, and a slightly richer Jet needle).

The concept behind the homo-pressure carbs was to remove the need to compensate for differences in atmospheric pressure due to altitude (richer jet in Denver vs. sea level Miami). As the pressure in the float bowl drops at open throttle, a much larger jet is needed in a homo-pressure carb.

The #97.5 main jet is definitely a round (N100/604 Reverse). A #150 round jet would be equivalent to a #275 hex. A #97.5 Hex would be lean, not too bad,around a #90 round. Both early and late carbs used 188 Series Needle Jets, which are for round head jets.

Along with the new carb, post 1973 used longer intake runners, which reduce the vacuum "signal" to the carbs, making them less responsive to throttle changes. This helped Suzuki detune the engine performance, making a bit more difference between the T500 and the GT550.

These changes (especially the longer intake runner) drove two other changes - a new air box (now serviceable foam, which you don't need to remove the air box to service), and adding a second frame brace under the seat, to attach the air box which had moved back a few inches.

[sbaugz]

trying out some different options for a fuel tank. What do you guys think?

First one is the stock tank.
Second one is a CB200T tank- I love these tanks. There are two chrome strips that mount on top of tank with a rubber piece in between. Looks real cool. Its a narrow tank. about the same length as stock
Third one is a XS750 Suzuki tank. these are nice looking tanks too. I like the cafe style knee cutouts. This is a very wide tank and its about 2 inches longer than stock tank.

[sbaugz]

I followed the advice above and purchased the earlier model rubber carb mounts. This brought my carbs about 2 inches forward and now gives me room for the UNI pod filters as shown above. I am having the oil tank made this week.

[sbaugz]

got a lot accomplished over the past few weeks.

Mounted up the Power Dynamo electronic ignition. Went together smoothly without any incident. I plan on running bike without battery. The new coils are mounted near the stock location, with the PD regulator mounted nearby under the tank.

Got the early model carb holders mounted up. This brought the carbs a couple inches closer to engine, which gave me room for my UNI pods- now they don't hit my frame bracing anymore.

I also removed all the unneeded tabs on the frame.

Decided I am probably going to use the XS750 tank as seen below. I think the look of that tank (with the built in knee-dents) is much more "cafe" than the stock Titan tank. Probably will go with chrome plating or possibly a chrome-look powder coat on the tank. Still undnecided on the seat, but will probably be an aluminum seat pan with matching chrome powder coat. The frame is going to be powder coated blue, so basically the entire bike will be polished or chrome with a blue frame.

I had a really nice oil tank custom made from a guy I found on ebay. He was super nice and whipped me up a tank - custom made to my dimensions and specifications within about 2 days for $100 shipped to my door. I got to pick location of cap, outlets, vents, including sizes and bend angles. Top notch quality. Got it mounted up under frame this week. Hopefully my Higgy chambers will be coming within the next few weeks. He said they should be done early january.

[titan performance]

I like the shape of that XS tank. The little Honda tank was far too small for the rest of the bike in my opinion. Old school cafes tend to be big tank, small seat....you would have ended it up with waaay too much seat if you had used that small tank. I'm following your build, and interested to see how it develops.

[sbaugz]

I like the shape of that XS tank. The little Honda tank was far too small for the rest of the bike in my opinion. Old school cafes tend to be big tank, small seat....you would have ended it up with waaay too much seat if you had used that small tank. I'm following your build, and interested to see how it develops.

thanks, I agree about the tank. I am still deciding how much of the rear frame rails I will cutting off. I am not a big fan of long, big seats. I would like to lose about 8-12 inches of rear frame rails but obviously I have to be careful of rear tire clearance.

I am leaning towards one of these "alloy" seats so I can have it polished or powder coated to match tank.

Legendary Sprite Alloy seat:



Bedlam Werks seat




leaning towards the bedlam seat. I always liked the squared off look in the back. In some ways, similar to the H1R and H2R seat pans with a square rear end. Makes it easier to inset some taillights too. Further updates to follow::::

[titan performance]

The US style is to have a shorter rear end than we do here in the UK....bear in mind you may want to hide some bits away under the seat hump.

[sbaugz]

The US style is to have a shorter rear end than we do here in the UK....bear in mind you may want to hide some bits away under the seat hump.

I have noticed the differing style trends of US versus the folks across the pond. I tend to like really small seat pans personally.

The beauty is, I don't actually have anything I need to hide. With the power Dynamo, I am not running a battery. The regulator, coils, fuse box, and flasher relay will all tuck under the tank between the upper and lower frame rails under the tank. There really isnt anything else left to hide.

[rngdng]

If you are using the short intake rubbers, be careful setting up the jetting. I changed my GT500 to short intakes without changing the jetting, and the mains ran too lean which caused a seizure....(ask gyrocfi)



Lane

[sbaugz]

If you are using the short intake rubbers, be careful setting up the jetting. I changed my GT500 to short intakes without changing the jetting, and the mains ran too lean which caused a seizure....(ask gyrocfi)



Lane

sounds good. Thanks for the advice. I rebuilt my carbs with 120 main jets per Titan Performance's recommendations. My bike will have UNI filters, Higgspeed Chambers, and now the shorter intakes. Should I go up even more on the mains?

[rngdng]

I don't really know, just start fat and work down as usual.



Lane

[jabcb]

That oil tank looks interesting. Might work on our GT250 cafe build.

[sbaugz]

That oil tank looks interesting. Might work on our GT250 cafe build.

I can give you his contact info. He will make it any way you want. 4" or 5" diameter. Any length. Any fittings. He will put the filler cap and mounts anywhere. Pressure checked and shipped out for $100. I got mine five days after ordering. Let me know.

[titan performance]

You'll not melt anything with 120's. But that's a starting point. On my own bike, I use 115s with pods and pipes, and have used the motor very hard without issues. I have also increased pilots to 35.