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Post Info TOPIC: 325 conversion - exhaust and other
jon


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325 conversion - exhaust and other
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Hello

Im preparing for the installation of Thumper Racing 325 big bore kit. Inspecting everything as I take the bike apart as you would. Noticed there is a 17mm ID x 60mm long back pressure restriction in the exhaust header. See pic. Has anyone removed or modified that in any way ?

Per previous, Im planning to mill the cases without splitting. Here is pic of plastic swarf collector inserted. Plan is to seal up before machining with candle wax. Will take some pics while on the mill.

 Third pic is the motor on a fabricated support. Will need this to clamp down to mill bed, but also makes the motor hell of a lot easier to work on.

Jon

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Perth , Australia



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Jon, this link tells you all about "uncorking" the TTR:-

CLICKY THING

I'm sure that Brian will be interested in your 325 conversion, especially your proposed modus operandi. He's converted his and a friend's TTR and has had a few problems, mainly with oil retention.

Brian's currently on holiday but should be back soon.

Keep the reports and pictures flowing because we're all interested.

Martyn



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Lin


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Cut around the pipe about 5mm from the end. The restrictor falls out and the bike goes a lot better. Fit one of Brian's short pipes and it goes even better again.

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jon


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ok read the threads and take the advice. the restrictor is gone this evening..

There is also this bulbus item attached to the carby intake hose. See pic..my mate says its like a pulsation dampener, supposed to smooth out intake pulsation? sounds like a sales line..


Anyone know if removing it affects the bike performance adversely ? Having it gone would make carby manipulation for jetting a whole lot easier.. ?

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Perth , Australia

Lin


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It's called a resonator. It's not a sales line, they are generally used to quieten down intake roar. Don't know if removing it will affect performance. Our 2010 TTRs aren't fitted with resonators.

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jon wrote:

ok read the threads and take the advice. the restrictor is gone this evening..

There is also this bulbus item attached to the carby intake hose. See pic..my mate says its like a pulsation dampener, supposed to smooth out intake pulsation? sounds like a sales line..


Anyone know if removing it affects the bike performance adversely ? Having it gone would make carby manipulation for jetting a whole lot easier.. ?


 I guess the only real way to tell would be to try it on a dyno but that isn't realistic. I am not sure that any change in performance would be noticed. Let us know the result if you try it!

Any progress on the casings etc?

Brian



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Jon

How did your plastic swarf collector go?

Greg

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jon


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Hi Greg, there is plenty of room in there. I stuffed the crank case full of rags first, then put the swarf collector in there, then filled with candle wax. I used a vacuum, when doing the milling. I used a vacuum when pulling the swarf collector out and rags out. Pretty sure i didnt get any cuttings in the crank case. Anyway after I got the bike going I checked the filter strainer every few hours of running. There was some fine metal material, not sure if this was from milling or just general running in of new piston and rings. Ive done 630km of hard riding now and everything is good. See other post about that trip. see pics of milling operation, can see my hand holding industrial vac hose.

I am getting a oil weep from hair line crack in cylinder jacket same as Brian got on his. Not a big deal but annoying if you dont like dust collecting on a oil weep.

If you get Thumper to instal the 325 sleeve, i would investigate with them if a slight bias to cam chain gallery and rear of cylinder. Seems the left side (Brian) and front (me) are suspectable to the hair line cracks.

Jon

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Is your barrel still leaking after your rebuild using Three Bond?

Also, did you resleeve your barrel or did you get Thumper to supply it pre-installed and bored for the new piston?

Brian



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jon


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Thumper did the barrel and boring. I didnt use Three Bond as wasnt aware of it. Anyway the weep seems to come and go. hoping it will settle down, but not too fussed.
Regards
Jon

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jon wrote:

Thumper did the barrel and boring. I didnt use Three Bond as wasnt aware of it. Anyway the weep seems to come and go. hoping it will settle down, but not too fussed.
Regards
Jon


Ah - no. It was Bruce had the weep and used Three Bond to try and cure it. If he is reading this, did it work Bruce?

Disappointed to hear that your barrel cracked after getting Thumper to do the work cry



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