Author Topic: top tube frame mod  (Read 1208 times)

Offline haynes66

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top tube frame mod
« on: January 25, 2018, 09:04:43 PM »
ive had a quick search but cant find much info about this mod. after struggling to remove the frame from my F2 engine (on its side) i can now see the benefits. i have both read rep and britain frames lined up for powder coat but might be worth my while doing this mod now. any thoughts on butchering a pair of classics? it's not visible though so the purists wont foam at the mouth too much...
honda firestorm
silverwing 600 scooter
honda britain project
phil read rep project
YGS1 80cc yamaha
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Offline Nurse Julie

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Re: top tube frame mod
« Reply #1 on: January 25, 2018, 09:24:19 PM »
I can't remember the make but James H has fitted one.
LINK TO MY EBAY PAGE. As many of you know already, I give 10% discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

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Offline Nurse Julie

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Re: top tube frame mod
« Reply #2 on: January 25, 2018, 09:59:33 PM »
Gordon Frame Kit.......I knew it would come to me eventually  ;D ;D ;D
https://m.youtube.com/watch?v=CIMfpKsK0Ho
« Last Edit: January 25, 2018, 10:01:46 PM by Nurse Julie »
LINK TO MY EBAY PAGE. As many of you know already, I give 10% discount and do post at cost to forum members if you PM me direct.
https://www.ebay.co.uk/sch/julies9731/m.html?item=165142672569&rt=nc&_trksid=p2047675.m3561.l2562

LINK TO MY CB400/4 ENGINE STRIP / ASSESSMENT AND REBUILD...NOW COMPLETE
http://www.sohc.co.uk/index.php/topic,14049.msg112691/topicseen.html#new

Offline haynes66

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Re: top tube frame mod
« Reply #3 on: January 25, 2018, 10:08:48 PM »
that's the one! i knew i'd read about it somewhere.  bit steep at $175 though, especially as i need two
honda firestorm
silverwing 600 scooter
honda britain project
phil read rep project
YGS1 80cc yamaha
LE Velocette

Offline hairygit

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Re: top tube frame mod
« Reply #4 on: January 25, 2018, 10:09:57 PM »
Ordinarily I wouldn't fit one, but absolutely not to a Britain or Read rep, the people who pay good money for them would run a mile from a butchered frame. After all, Honda put that bracing under the main tube for a good reason, and I certainly wouldn't ride one like it. Do you expect to blow a head gasket or worse on a regular basis? If not, leave well alone, bolted in bits are never as strong as welding, plenty here have used them, but I wouldn't.

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Offline Moorey

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Re: top tube frame mod
« Reply #5 on: January 25, 2018, 10:14:18 PM »
I seriously considered it, but dismissed it. In reality how many times will you hopefully have to take the engine out or do top end work.

Offline haynes66

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Re: top tube frame mod
« Reply #6 on: January 25, 2018, 10:15:38 PM »
valid point. i'll stick with standard. i'll just have to bandage the frame really well when refitting. quite a squeeze though. but like you said, once theyre rebuilt, i hopefully wont need to take anything apart again
honda firestorm
silverwing 600 scooter
honda britain project
phil read rep project
YGS1 80cc yamaha
LE Velocette

Offline MCTID

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Re: top tube frame mod
« Reply #7 on: January 26, 2018, 11:18:08 AM »
Heres some info about the Honda Top Tube modification a US Dealer sells/ installs.....but there's nothing stopping you making up your own or getting a Local Fab Shop to machine the parts for you.....after all it doesn't look like rocket science to me.

I also agree that it wouldn't be advisable on a very valuable bike such as a PRR/ Sandcast etc as a 'purist' might be put off buying it in the future, but for a daily user/ track bike I can see the benefits.

http://carpyscaferacers.com/shop/body-parts-and-accessories/frame-adapter-honda/
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Offline archmill

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Re: top tube frame mod
« Reply #8 on: March 19, 2018, 09:47:54 PM »
Guy's, I made up my own frame kit in 2012 I think ( posted photo's at the time) and there was quite a bit of interest at the time. Now I've got my own machine shop and have made a few kits which are a lot cheaper than the Gordons kit from USA. Also remember Auntie Theresa will rip you off for import duty and then add VAT and then hold it to randsom with their 'approved carrier' with a fifteen quid delivery charge even after you have paid for delivery when you bought it in the USA.

Offline JamesH

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Re: top tube frame mod
« Reply #9 on: March 19, 2018, 10:48:10 PM »
Great work. Saw those listed on eBay only this week. Will def buy a kit and try it out...

Offline Bryanj

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Re: top tube frame mod
« Reply #10 on: March 20, 2018, 07:05:57 AM »
If you remove all the correct bits and get the engine at exactly the right angle they do come out with no frame damage, when it was a common thing(late 70'S) due to bad services causing cam damage I could do them on my own but that was a long time ago and what with arthritis and Guinness consumption I could not even remember what to take off the engine, never mind attempt the job!!!

Offline MarkCR750

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Re: top tube frame mod
« Reply #11 on: March 20, 2018, 07:59:53 AM »
Getting the frame back over the engine is really easy with the engine on it’s side, no struggle at all so although it’s always wise to protect the newly painted frame it goes on so easily its  almost unnecessary to protect, I can’t speak for removing the engine using the “on side” method because I stupidly removed the engine with the bike vertical and struggled like mad!.
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Offline Moorey

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Re: top tube frame mod
« Reply #12 on: March 20, 2018, 09:59:49 AM »
Even though I seriously considered doing it. Now I wouldn't by a bike that had, had it done. Its a short cut done for those racing and having regular top end work done

Offline neilg

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Re: top tube frame mod
« Reply #13 on: March 20, 2018, 02:23:34 PM »

 

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