T500 Jemco Chambers, look at picture,

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LexPaul
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T500 Jemco Chambers, look at picture,

Post by LexPaul »

The sound coming off these pipes is great but a hair bit loud. Would using that pipe wrap up on the top, near the headers, soften the sound any? I do pack with wadding as needed.

Also, I have a 14t x 33T sprockets and it's a bit slow off the line. I was thinking about going to a 13T x 35T set up. Does anyone have any suggestions. What do you like and why?

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1970 Suzuki T500 Titan Twin
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Re: T500 Jemco Chambers, look at picture,

Post by pearljam724 »

Wrapping the headers will do nothing for sound. The bike is flat off the line because of the 33 tooth rear sprocket. 35 will not improve that a great deal either. I would look to buy one between 42 and 45 to see good results. 14 tooth front sprocket is a good choice for the front. But, your rear is geared way too high, which over comes the good choice of the front sprocket tooth count. The only thing that is going to dampen the sound of the chambers. Is more internal packing. Make it thicker.
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Re: T500 Jemco Chambers, look at picture,

Post by jabcb »

I think there is something to be said for staying within the range of optional sprockets.
The smallest front & largest rear that Suzuki offered were 13 & 39.

Another forum member probably give you some good suggestions that are between stock & 13/39.
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LexPaul
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Re: T500 Jemco Chambers, look at picture,

Post by LexPaul »

According to the parts book, posted on the compedium, 13 x 35 is the smallest front and largest rear, so I feel like that would have to offer the best acceleration without compromising anything, otherwise the engineers would have added additional options, am I right or wrong on this??
1970 Suzuki T500 Titan Twin
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Re: T500 Jemco Chambers, look at picture,

Post by Vintageman »

If packing in jemcos is new as mine still loud. I think the silencer tubes are a little bigger in diameter than needed.

I run 35 tooth on back or whatever 2 more than stock is. OK off line for street use and good cruising ability highway. I did not want to go smaller on front sprocket since swing arm so long and when chain loose it can rub on it. Not sure why you could not run 37 rear?
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Re: T500 Jemco Chambers, look at picture,

Post by Bloop2 »

You have already dropped the front sprocket by 1 from the stock one. Stock was 15/33. I wouldn't go any smaller on the front, maybe up the rear if you're looking for a bit more acceleration.

There's a great explanation on gearing ratio's at Bike Bandit, what you can expect by changing to different sprockets.

http://www.bikebandit.com/community/gui ... -sprockets" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
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Re: T500 Jemco Chambers, look at picture,

Post by pearljam724 »

LexPaul wrote:According to the parts book, posted on the compedium, 13 x 35 is the smallest front and largest rear, so I feel like that would have to offer the best acceleration without compromising anything, otherwise the engineers would have added additional options, am I right or wrong on this??
Manufacturers offer nothing in reference to gearing options on one particular model. Options come via aftermarket or using a different tooth count designed for another model. Those options allow an individual to find what characteristics he's looking for from any make or model. Your bike feels too flat off the get go for you. You simply gear it down some more. Doing that by less teeth count on the front or more on the back. Or a combination of both. All bikes work the same. Regardless, of model or cc. There is a point, where gearing can only do so much depending on the power a motor produces. 33 teeth is a very high geared sprocket for any bike. That's a good sprocket for long, straight, flat highway rides on a bike that produces good power. It will produce a higher top end speed with good fuel mileage. But, it's gonna be terrible at everything between. Like acceleration power to accomplish top speed or accelerating from a stop. Lower gearing on these old bikes is the way to go. Unless, you do a lot of flat tour riding. They simply don't produce enough power and are too heavy for a high gearing combination to make sense. Especially on a street bike that's mainly ridden locally. 33 teeth is very high for a bike that produces 125-150 hp and weighs nearly 100 pds less. Consider your Titan is not even in that ball park. To get the best acceleration out of what little hp it produces you're going to have to go lower on the gearing.
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Re: T500 Jemco Chambers, look at picture,

Post by titan performance »

I have experimented with sprockets over the years, and once fitted a 42 on the rear because I wanted to pop wheelies off the throttle. It worked, but I soon reverted back to the smaller rear because the 42 was way too low. I have owned 500's for nearly 40 years now, and over that time have had countless opportunities to compare the performance with comparable models. In my experience, the 500 beats a 380 everywhere....and is very close to a 550 in all departments. Top speed indicated will likely be between 105-110 on a good day with factory gearing. The 500 is no slouch and always able to hold it's own with similar capacity machines of the era. I could see an argument for maybe 2 teeth at the rear to help it pull top a little easier, but I think more than that will shorten the gears too much on a road bike. I would suggest giving it a bigger handful to get it spinning.....but if you are still convinced it's flat, maybe there's another issue. Have you altered the jetting at all for the pipes? I have never owned Jemcos, but fitting our own pipes without adjustment will not get the best results. Even with the stock airbox, you would need to increase the jets to eliminate that slight reluctance you feel low down due to a slightly lean mixture.
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Re: T500 Jemco Chambers, look at picture,

Post by tz375 »

Titan,
What gearing combinations did you try and what worked for you? I have no idea what front and rear are fitted to this particular bike and it's possible that a previous owner changed to higher gearing (lower numerically) from stock.
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Re: T500 Jemco Chambers, look at picture,

Post by titan performance »

To be honest, the only larger rear I used was the 42, but I coupled it with 13, 14 and 15 on the front. However, 42 was just too big, and made the the lower gears too short in my opinion, even with 15 on the front. I have used all of those fronts with a 33 rear. I used to race one of my bikes over an eighth of a mile every weekend in the early 80's, and I opted for a 13 front to give it a bit more urgency off the mark. I didn't stick with that combo too long though, as I fitted some mildly ported barrels and Barton heads, and with a few extra ponies on tap, I found that 14/33 suited me perfectly. I regularly clocked 8.6 over the eighth, which was quick enough to beat all the other half litre machinery at that time. The GPZ 550 was the tool to own in the early 80's where I live, my old smoker smoked 'em every time. On the road I could achieve an indicated 120, and actually, still can ! Acceleration these days is down though, because the jockey has grown some !
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Re: T500 Jemco Chambers, look at picture,

Post by LexPaul »

Thank you all for an excellent discussion on gearing,,
1970 Suzuki T500 Titan Twin
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Re: T500 Jemco Chambers, look at picture,

Post by alfiemorris »

So 14 and stock 33 might work for me? In Cornwall UK, we have lots of hills, up and down, and 15/ 33 makes getting away pretty difficult. 14 tooth sprockets hard to come by now I'm told, perhaps a 35 or 36 rear might be the answer? Any advices please?
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Re: T500 Jemco Chambers, look at picture,

Post by Vintageman »

I run stock front and rear sprocket now on my T500. It was 35T on rear for a while (6% lower geared). With stock 33 it accelerates off the line just as well to me. I live on the border of New Hampshire and Vermont so many hills as well. With factory gearing, I find 5th gear is better for running Interstate 91 or 89 around me at ~70 mph. The 6% lower rpms puts me in a better rpm range for easy on the body cruising. Still , the bike has plenty of torque to accel up a grade even in 5th. I suspect it could go even a little more higher geared.

I think the key is to run stock ignition timing. if you run retarded, for your reasons, you won't have the same midrange power. Also my engine is fairly fresh, all new brass in carbs, stock air box and just enough miles since to be broken in well it feels now. I do run Jemcos.

For me, mildly aggressive street riding and nice cruising manners, I am respecting stock gearing for some my bikes these days. T500 being one of them. Others I go higher geared and others lower geared

The best thing is try many and see what you like for your riding needs.
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