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Post Info TOPIC: 350cc Big Bore Kit for the TTR250 - updates and gossip!


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RE: 350cc Big Bore Kit for the TTR250 - updates and gossip!
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I've got just over 4000 miles on mine since the 350 was fitted. Just seems to get stronger all the time.



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mossproof wrote:

Thanks for the update. Good to hear things are running well (including the carb mod).
I don't think I'm a sensitive (or fast) enough rider to feel the benefit of gold valving the forks, but as I've more or less run out of other things I want to modify, I suppose I should try!
Cheers,
Simon.


 

I haven't read through to see if anyone replied but, emulators may be the best modification you can do to damper rod forks.  No matter how fast or slow you ride.   The fact that the emulators will force you to buy new springs, probably better suited to your weight, has to be part of it.

 



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In the Riverina.

'73 RD250, '76 RD400, '80 XS1100, '81 RD373LC, '96 Tiger 900/sidecar, '02 TTR250, and another XS11 - this time a chain drive Period 5 race bike that may be ready to race in early '22, or '23??



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mossproof wrote:
JOHNYBOY wrote:

why not vent it to atmospere up the frame & to the back like they did on a lot of british bikes


 

Well the breather sucks as well as blows - every time the piston goes up and down, so you risk drawing dust/water into the crankcases, quite apart from the oily mess that will build up (not a problem with old British bikes, which were an oily mess from the factory


 

Add a filter to the end.  You'll see it on most road race bikes.  They have a small in-line catch bottle with a filter down line of that.  Of course, that depends on how deep you want to go and where you're going to put it.  S'pose that's why the manufacturers stick the crankcase vent into the airbox.

 

 

Why am I looking at this thread?  Well, I have just picked up a dismantled engine... the brain is working.  Just reading.  Probably wont happen as I've got too many other irons in separate fires.  Surely enough to keep me going for a couple of years.  I'd best get into one...

 

 

 

 



-- Edited by tripodtiger on Saturday 30th of July 2022 02:28:04 AM

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In the Riverina.

'73 RD250, '76 RD400, '80 XS1100, '81 RD373LC, '96 Tiger 900/sidecar, '02 TTR250, and another XS11 - this time a chain drive Period 5 race bike that may be ready to race in early '22, or '23??



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Morning gents! I just did a compression check. I'm about 100 psi dry and about 115 wet. I am guessing its more valves than rings.

I find working on the bike in the parking area of my flat a real challenge.

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Oh, the bike also makes one hell of a banging noise on start up. It sounds like the pistion is hitting something something. Once the engine catches it goes away. Any ideas?

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Got the engine apart.  I was really surprised with the amount of carbon build up.  I'm assuming it's not normal and because the bike is running too rich?

 

The barrel looks good, but there is a tiny bit of wear on the top of the photo.  I can just feel it with a finger.  Just...

 

 

Anyways, time to figure out how to get the valves off!  



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