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Old 2nd October 2007, 06:52   #16
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Nice work. Good to see people doing more and more DIY.

I have a few suggestions to make.

Quote:
Originally Posted by Shreeram View Post

Specially Fabricated Exhaust Bringing Exhaust Gases from both Exhaust manifolds towards the right – hand side.

This is going to hurt performance badly. I assume you might not be aware of two-stroke exhaust design so here's a brief explanation of what will work better. If you want a single exhaust, you need to merge both header pipes into a Y of about 45 mm outlet diameter and then run it into the front cone. A center section diameter of 100 mm works well on the long stroke jawa engine (roadking is different). The cone angles seem to be ok. Run a single 22 mm diameter rear pipe into the muffler. This is very important. The length seems to be fine. I'd also make sure that there are absolutely no leaks anywhere (would prefer a single piece welded chamber from exhaust port onwards).

Good luck and keep us posted.
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Old 2nd October 2007, 09:11   #17
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A beautiful bike gets it's due. That would be a more apt title for this thread. Great job, shreeram. waiting for the final pics. One suggestion from my side. The beauty of the Yezdi was it's double silencer.
cheers
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Old 2nd October 2007, 09:59   #18
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Nice work Shreeram. All the best for your project. I agree with everyone keep the twin silencers. Also I think the rear tyre is wrongly mounted.
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Old 2nd October 2007, 10:57   #19
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Nice work Sreeram, it looks fantastic! And I prefer the non-Yezdi tank, it suits the look more.
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Old 2nd October 2007, 15:01   #20
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Amazing work there bro. Always had something for Java/Yezdi. Would love to see how its gonna turn out when everythings done.
BTW, as someone mentioned earlier, maybe u can think about sticking to the OEM twin exhaust, rather than this custome one. Just my suggestions though...
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Old 2nd October 2007, 15:19   #21
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best keep it up, but one change i sugest u is pls retain the original twin silencer set up this one looks very odd, all the best post more pic.
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Old 2nd October 2007, 15:54   #22
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@BlackPerl
Highwayblaze
Payam
Rohan
Nitin
TheMag
Gordon - Yes the Tyre is wrongly Mounted. Will be rectified.
iraghava
souljah - The Joy of DoingIY is very rewarding.

Justdevil - Yes thats the metal - mesh filter but with
Cotton sponge in between the two mesh layers.

@V13pr - BothExhausts are running on Expansions.

1) The Swingarm is from Unicorn.

2 ) The MonoShok is custom Made!!!!.

Thank You All and any others, if i have missed some.
Will update with new pics soon.

---------------------------------------------------
One Note For All - Keep Giving Your Suggestions.
My Bike Is So Designed That I can Put Back or Remove & Replace
anything & everyting within a few Min's. Everyting is "BOLT ON"

eg. The Original Twin Silencers.
The Round Tank

---------------------------------------------------

@Ripper , Steeroid , Mpower , EsteemLover

I had tried those Twin Silencers Earilier.
See the Photos Posted Below.
I can & will revert back to the orginal exhausts at any point of time without any modification - ie weilding/cutting.

Will Post Final Pics with Twin Exhausts & The Rounded Tank Installed.

The Wide Handle Is in Order.

------------------------------------------------------------

I am not a student of Engg. I am designing it on basis of my some research & artistic view.

May be the exhaust is not designed Scientifically. But i have tried to implement simple & common techniques & sense.

@Vabs78
@ananthkamat - Lets discuss the Exhaust.

Heres an overview of the Exhaust Design.



as you can see, Inside it is so designed that it does not hamper the Flow of the exhaust to a certain Extent.
I rode this bike in the current condition for some time now on trial, Long Distances too.
It is going Fine. The exhaust does not seem to hamper the performance, infact it has increased it.

Many people here are earging to keep the original exhaust. So lets try that too.
-------------------------------------------------------------

Thanking You And Looking Forward to Your responses.

Here are old pics.
















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Old 2nd October 2007, 16:10   #23
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great work shreeram.. i would suggest if you are going for chambers then use two chambers on both the sides instead of on one side.. will appeal better and sound better and perform better too...also try to get a V shaped handle bar for that cruiser look...
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Old 2nd October 2007, 16:24   #24
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great work shreeram. the bike with the round tank looks very nice. the exhaust looks odd on the bike i think like most people have mentioned the original twin exhausts would suit this project better. you could customise it shape wise to suit the bike. something like the suzuki bulevard exhaust or like the BKing shape wise.
keep up the good work. all the best.
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Old 2nd October 2007, 19:14   #25
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Quote:
Originally Posted by Shreeram View Post
Here are old pics.


Will look so much nicer if you went back to Chrome exhausts with some custom work done either to the ends or at the joints to make it longer. All you will then need is a stylized metal piece that starts at the Tank and covers (1) the monoshock and (2) the gap between the engine and the frame.

You could also make a LONGER rounded tank so that you have less area to cover up with spare metal.

Last edited by Steeroid : 2nd October 2007 at 19:16.
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Old 2nd October 2007, 20:08   #26
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Quote:
Originally Posted by Shreeram View Post
Here’s How it Looks like when all things assembled.
Shreeram,
The expansion chamber is not designed for improving flow of the exhaust, so we are not talking about hampering the flow of the exhaust here.

Here is briefly how it works:
At the time of exhaust stroke, a pressure wave is created at the exhaust port. The diffuser cone uses this pressure wave and its gradually increasing area of cross-section to create a -ve pressure wave (suction). This helps in sucking out the burnt gases from the cylinder so as to provide a clean environment for the incoming charge.

But this can also suck out the un-burnt charge. To prevent this baffle Cone is used. Due to the gradually decreasing area of cross-section baffle creates a +ve pressure wave. If this wave reaches the exhaust port at the right time then it prevents fresh charge from being sucked out.

The distance between diffuser and baffle (belly length) determines the time difference between -ve and +ve pressure wave.

The header pipe design influences the flow of exhaust and the tailpipe length determines the backpressure and the optimum RPM.

Now, with your design,
- Lengths of two header pipes is different, due to this the time taken for the pressure wave to reach the diffuser will be different for each cylinder. But as both the cylinders will be running at same speed, the exhaust tuning will be wrong for any one of them.

- One of the header pipe is connected directly to the belly so the diffuser cone will not be working for this cylinder. As only the baffle is working for this cylinder you won't get good combustion.

- The tailpipe is separated before the baffle cone ends. This will prevent the generation of a smooth +ve pressure wave.

Experts can confirm my analysis or correct me if I am wrong. I would say that this exhaust will not only hamper the performance but may also cause damage to the engine.

I really appreciate your effort and I would like your project to work. Best of luck.
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Old 2nd October 2007, 21:43   #27
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Quote:
Originally Posted by vabs78 View Post
Shreeram,
The expansion chamber is not designed for improving flow of the exhaust, so we are not talking about hampering the flow of the exhaust here.


Now, with your design,
- Lengths of two header pipes is different, due to this the time taken for the pressure wave to reach the diffuser will be different for each cylinder. But as both the cylinders will be running at same speed, the exhaust tuning will be wrong for any one of them.

- One of the header pipe is connected directly to the belly so the diffuser cone will not be working for this cylinder. As only the baffle is working for this cylinder you won't get good combustion.

- The tailpipe is separated before the baffle cone ends. This will prevent the generation of a smooth +ve pressure wave.

Experts can confirm my analysis or correct me if I am wrong. I would say that this exhaust will not only hamper the performance but may also cause damage to the engine.

I really appreciate your effort and I would like your project to work. Best of luck.
Thank You for your time & the detailed explaination & correcting Me.
Would have been good if someone like you was there to guide me while
desiging the exhaust.

One thing. As per your write up it seems you think the yezdi has twin cylinders.
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Old 2nd October 2007, 21:50   #28
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Hi As per the suggestions from most of you people.

I will be using The Original Twin Silencers - Chromed @steeriod

That way it will also look nice & prevent it from damaging the engine if it is right now as pointed out by ananthkamat & vabs78 - thanks.

For the tank - i will Paint Both & Use one of them by interchanging as per my wish.
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Old 2nd October 2007, 21:59   #29
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Quote:
Originally Posted by Shreeram View Post
One thing. As per your write up it seems you think the yezdi has twin cylinders.
Oops, sorry I got it mixed up with the 350cc. Thats what happens when you don't have hands on experiance.
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Old 2nd October 2007, 22:44   #30
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@Shreeram: Is this some different kind of metal-mesh filter or do all them filters have a cotton layer? Most sellers and 2-stroke experts have told me to refrain from using metalmesh. I don't know the reason but they always suggest cotton or foam ones.

@ananthkamath: Doesn't the two into one design still hamper performance, by making scavenging a little more difficult? Wouldn't the stock exhausts work better? Or would a properly designed 2 into 1 be good enough?
Just a thought!
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