Author Topic: Scott Clough's 127mph rd350  (Read 464 times)

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Offline Barnett

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Scott Clough's 127mph rd350
« on: April 06, 2019, 01:28:01 AM »
For those who havn't seen this article an interesting read!
Note the standard silencers!
Brave bloke.

http://nebula.wsimg.com/c213ccec79d4cf41edde0af042a9b144?AccessKeyId=453586276B777C7A85FF&disposition=0&alloworigin=1


Yamaha 1974 RD125 (AS3) fully restored 2018 on road
Kawasaki 1977 z650 B1 on road
Yamaha 1972/3 U.S. early RD350 ongoing project.

Offline twostrokelooney

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Re: Scott Clough's 127mph rd350
« Reply #1 on: April 06, 2019, 08:22:51 AM »
Amazing, good find there. Think I'll get the files out later today... ;D ;D ;D
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RD350 (1973)
RD250E
TZR250 2MA YPVS
Z1000J3

Online 5port

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Re: Scott Clough's 127mph rd350
« Reply #2 on: April 06, 2019, 05:26:41 PM »
I should be careful with the details of the porting in that.  The article says the exhaust ports are raised 4.5mm!  That could put you firmly in TZ territory.  I can't really square the description with what is known, I measure most RD350 and RD250 aircooled cylinders and get the same as Ed Erlenbach shows on his tuning website. In that article they quote 32mm as standard for a RD350 but I usually find 30 to 30.5mm.  Well, if you are working with 32mm, less 4.5 does give 27.5... about the same as a YPVS350 with the Exhaust power valves stuck fully open.  Also 2mm off the heads and recut to give 18cc is a considerable compression, although they don't mention what squish he is using.  Overall, nothing there that would surprise but, also not all the detail that you need to go porting!  ???

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Online betty foRD

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Re: Scott Clough's 127mph rd350
« Reply #3 on: April 06, 2019, 10:19:02 PM »
4.5 up EP is ok on standard pipes because the stock exhausts are so long. Power band at about 9K and is typical of proddy tune of the day when standard pipes were required.

But I agree if you can have diferent pipes , don’t go taking more than 3mm off the port.
Rev 'em till they rattle

Online 5port

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Re: Scott Clough's 127mph rd350
« Reply #4 on: April 07, 2019, 08:19:07 AM »
I see where they got the 32mm Ex port height from now, it is from the R5.  ::)  So folks, do not take 4.5mm off your RD350 pots, that could leave you with a useless 25mm.  :o  To me, that article is like many sensational bike mag "tuning" articles, it only tells half the story and then, gets details wrong.  If anyone is seriously interested in tuning, read all the info you can find then, go to someone like Mick Abbey and see what he can do for you!  :)     Of course, if you want to and can afford to experiment on your own......expect to spend £££££ before getting good results.   ;)

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Offline SupeRDel

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Re: Scott Clough's 127mph rd350
« Reply #5 on: April 10, 2019, 07:57:06 PM »
Where in the article does it say its done 127mph.
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Offline tractorman

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Re: Scott Clough's 127mph rd350
« Reply #6 on: April 10, 2019, 08:42:44 PM »
Right at the end.

Offline Scullyh2

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Re: Scott Clough's 127mph rd350
« Reply #7 on: April 10, 2019, 08:44:05 PM »
It’s in the bold lettering. Right under picture to the right :)

Offline SupeRDel

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Re: Scott Clough's 127mph rd350
« Reply #8 on: April 14, 2019, 05:44:09 PM »
Right at the end.

Right at the end it says what has been done "computes" to 127mph. That fact is placed right at the end

Stick a 10 stone rider on it and try and get that 127 - No where does it say its actually done 127mph.

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