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Old 2nd April 2007, 19:27   #31
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Is that a shorter header pipe or am I seeing things?
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Old 3rd April 2007, 13:03   #32
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Originally Posted by ananthkamath View Post
Is that a shorter header pipe or am I seeing things?
Yes, that's a shorter header. Temporary setup with stock muffler, will change over to a megaphone later.

The test run was satisfactory the torque is visible all over the powerband and pulling it means i can make the gearing taller. Another thing i noticed is that the i'm holding the handle steady but the bike's tail is going like a snake's tail at max velocity. Or more like the *** shakes you see in the hip-hop vidoes. The frame has to be trued, there's a slight bend in the downtube.

Apparently the 180 jet is a bit richer even with the needle at the leanest position so when i hold open the throttle at wot the bike flutters and when i close back the throttle the power picks up.

In the last pic Jk had posted you can see the head leaking after the ride. The acceleration was pretty strong initially, when the head was not leaking, and on the level ground i was leading jk for a while, but then later i lost the power a bit and on the downhill section he overtook me. But after that the power never came back like the first time.

With a foolproof head leak stopping technique, better manifold, better carburation and higher compression things could definitely improve.
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Old 7th September 2007, 14:03   #33
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Hi Guys
Nice Effort
But Did You change the timing and other CDI related things ??
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Old 26th May 2008, 10:22   #34
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Ahhh so long since the early days. Got a lot more to update regarding the Bull. She's running beautifully now. Done a recent Trivandrum Cochi trip on the Bull and the performance was too good, got a real nice fuel average too.
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Old 29th May 2008, 20:39   #35
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Hi Sankar, please forgive my naive query, but why isnt there a decompression lever on your bike? Did your mods remove the need for one?

ps: that is one ripping sound your bike has
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Old 29th May 2008, 20:43   #36
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Srijit, the space usually reserved for the decompressor is now occupied by a second spark plug (bosch super 4). Hence there is no space for a decompressor and thus no decompressor lever either.
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Old 30th May 2008, 09:59   #37
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So how do you get the engine to turn over? By kicking slowly/softly till the needle is in the green?
Or has that characteristic changed?
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Old 30th May 2008, 10:26   #38
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The only way to get it turn over is to kick it hard. If the Amp needle is in the centre then it will turn over without any major force on the kickstarter and it will start. If the ammeter needle is in the negative you have to kick it really hard to make it turn over and start.

When I had the valves and the seat redone last year the compression was so high that i could stand on the kicker when the ammeter was in negative. And the only way to decompress and thus start was to put the bike in 1st gear and slightly roll it backwards (sitting on the saddle). The bike would make a loud "phisssh" sound and the ammeter needle would be in the center.

The compression ratio is higher than a stock bull coz of the shaved head and the block. I tried running without a headgasket before on my old block and it was lapped to perfection, and it was partially succesful. But the compression was too high and eventually it self destructed. Now i'm using ultra thin custom copper headgasket, the advantage is that it doesnt leak and i can use layers which will help seal the combustion chamber perfectly and there won't be any compression leak. The only thing the copper gaskets seal is oil from the push rod tube and the outer part of the cylinder. In most std bullets the copper gasket seals the compression to an extent, which is okay with the normal compression but not with high compression.

And now the bike is running a revised cam timing. The effects are slightly lower initial pickup and really good top end. I have also added a megaphone exhaust (similar to the goldie pipe but not a goldie type), the megaphone does make it's presence felt and there sure is a gain. Does 80+ in second gear This is waaay better than before.
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Old 30th May 2008, 15:28   #39
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Hello!

What kind of Mileage do you get in the city/highway after all these mods?

-Ashwin
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Old 30th May 2008, 16:09   #40
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Quote:
Originally Posted by spyking View Post
Hello!

What kind of Mileage do you get in the city/highway after all these mods?

-Ashwin
Thats the fun part!! I get around 26 to 27 if i rip on the highways. And generally inside the city i get around 30-32 as i don't get the chance to open up completely.

The highway figures i have quoted from my recent trip to Cochi.

This is due to the increased efficiency.

Last edited by Sankar : 30th May 2008 at 16:22.
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Old 30th May 2008, 17:11   #41
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He he, thanks for the info Sankar. Maybe next time I can take it for a spin...
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Old 23rd April 2009, 17:07   #42
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Quote:
Originally Posted by Sankar View Post
Srijit, the space usually reserved for the decompressor is now occupied by a second spark plug (bosch super 4). Hence there is no space for a decompressor and thus no decompressor lever either.
I saw a similar modification on one of the Enfield communities on Orkut. The guy had connected the decomp cable somewhere near the tappet cover. A similar arrangement is used in the AVL engine. Maybe you should try it out.
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Old 23rd April 2009, 20:12   #43
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Quote:
Originally Posted by pedrolourenco View Post
I saw a similar modification on one of the Enfield communities on Orkut. The guy had connected the decomp cable somewhere near the tappet cover. A similar arrangement is used in the AVL engine. Maybe you should try it out.
What was the orkutian's name/id?

Sankar sold his bike and anyway, his bike didnt have a decomp lever.
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Old 24th April 2009, 21:37   #44
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Quote:
Originally Posted by jkdas View Post
What was the orkutian's name/id?

Sankar sold his bike and anyway, his bike didnt have a decomp lever.
It was quite a while ago. Let me search. Just wondering if I'm allowed to post the link here if I find it.


@jkdas
You can check these threads out
http://www.orkut.co.in/CommMsgs.aspx...4993&kw=Decomp


http://www.orkut.co.in/Album.aspx?ui...aid=1218440560

Someone has done a twinspark conversion with the decomp modification.

Mods please delete the next post.

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Last edited by pedrolourenco : 24th April 2009 at 21:56. Reason: Posted a new post by mistake
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Old 24th April 2009, 21:54   #45
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@jkdas
You can check these threads out
http://www.orkut.co.in/CommMsgs.aspx...4993&kw=Decomp


http://www.orkut.co.in/Album.aspx?ui...aid=1218440560

Someone has done a twinspark conversion with the decomp modification.
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