gt380 with a featherbed frame? Or a Seeley?

Retro, Wild, Cafe, etc. The stuff only your imagination can come up with.

Moderators: oldjapanesebikes, H2RICK, Suzsmokeyallan

sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

gt380 with a featherbed frame? Or a Seeley?

Post by sportston »

Does anyone know of a good frame that would fit a gt380 lump? I was considering making a special. Perhaps with a Seeley or a featherbed or similar. I have no idea what would fit a GT380 motor. Has anyone got experience in this area?
User avatar
garry55
Yeah Man, the Interstate
Posts: 629
Joined: Wed Jan 01, 2014 2:04 pm
Country: UK
Suzuki 2-Strokes: GT750 hybrids (x2) RGV500

Re: gt380 with a featherbed frame? Or a Seeley?

Post by garry55 »

If a H2 motor fits, a GT380 will............

Image

Suzuki GSX-R400 GK76A frame :up:
Garry


I'm addicted to brake fluid, but I know I can stop anytime.
User avatar
tz375
Moto GP
Posts: 6204
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: gt380 with a featherbed frame? Or a Seeley?

Post by tz375 »

Spondon made some nice frames for the Barton GT380 based race bikes. A featherbed is a large and heavy frame. A Seeley might work or a Dresda frame or maybe even an RD350/400 but you would have to check the dimensions.

You could also keep the stock engine cradle and build a new frame around that.
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: gt380 with a featherbed frame? Or a Seeley?

Post by Zunspec4 »

Hi sportston,

Not an insignificant project :up:

You can fit just about any engine in any frame if you have the engineering, or project management (i.e pay someone else to do it) skills and budget. You are not going to find a turn key solution to a GT380 special but there is a lot of fun to be had in creating one yourself. There are a bunch of outfits that could make you a replica frame (I would go for a Seeley, but I am very biased). If you commissioned a frame the builder would probably use your crankcases + barrels on their jig to establish mounting points and pipe clearances etc.

Starting with only an engine........ you will need deep pockets, maybe in the range of £5000 - £10,000. Sorry about that :D

Cheers Geoff
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: gt380 with a featherbed frame? Or a Seeley?

Post by sportston »

Zunspec4 wrote:Hi sportston,

you will need deep pockets, maybe in the range of £5000 - £10,000. Sorry about that :D

Cheers Geoff
OUCH!!
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: gt380 with a featherbed frame? Or a Seeley?

Post by sportston »

garry55 wrote:If a H2 motor fits, a GT380 will............

Image

Suzuki GSX-R400 GK76A frame :up:
Hmmm. Looks good but i was thinking something that looked a little more 1970s. However, I will think about that one....
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: gt380 with a featherbed frame? Or a Seeley?

Post by sportston »

So far a Dresda frame seems likely to offer best value for money, but it will be a long while before i can put my plan into action. Sniff sob
User avatar
tz375
Moto GP
Posts: 6204
Joined: Mon Nov 03, 2008 10:47 am
Location: Illinois

Re: gt380 with a featherbed frame? Or a Seeley?

Post by tz375 »

Or build a jig, buy some Reynolds 531 or 631 or whatever they sell now and make it yourself. Or get some 953 stainless wwich offers an even higher strength to weight according to their website.
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: gt380 with a featherbed frame? Or a Seeley?

Post by Zunspec4 »

sportston wrote:So far a Dresda frame seems likely to offer best value for money, but it will be a long while before i can put my plan into action. Sniff sob
I have no clue as to the length of the waiting list for a Degens Dresda frame so order now and start saving :D

When you start with a virgin frame you have an open canvas to do what you want but a bunch of thinking/design/fabrication time to invest (and money)

There is a lot to do starting from this:
Image

Cheers Geoff
sportston
Expert racer
Posts: 1119
Joined: Wed Jul 10, 2013 12:04 pm
Country: England, UK
Suzuki 2-Strokes: FZ50, GP100, RG125 Gamma, GT380, Bandit 1200S

Re: gt380 with a featherbed frame? Or a Seeley?

Post by sportston »

I did think of making my own but... I don't have the expertise or equipment. I think on something as major as a frame I should leave that to the professionals.
Nice frame Geoff. Is that a seeley?
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: gt380 with a featherbed frame? Or a Seeley?

Post by Zunspec4 »

sportston wrote:I did think of making my own but... I don't have the expertise or equipment. I think on something as major as a frame I should leave that to the professionals.
Nice frame Geoff. Is that a seeley?
Hi sportston,

Yes, a Seeley replica frame made for the T/GT 500 engine. These were an original option from Colin Seeley so there are several people who produce replica's (A Tichmarsh frame is the only one officially acknowledged by Colin). There is no fundamental reason why the engine mounts could not be modified for a GT380, or better still incorporated as part of a new frame. A link to my build photos below, you can see some of what was done.

https://flic.kr/s/aHsjCh8pt9

Cheers Geoff
Last edited by Zunspec4 on Sun Mar 12, 2017 11:55 am, edited 1 time in total.
User avatar
Alan H
Moto GP
Posts: 3160
Joined: Thu Feb 16, 2012 11:50 am
Country: England
Suzuki 2-Strokes: 4 x GT550s - J, M, A, B.
Location: The Republic of South Yorkshire

Re: gt380 with a featherbed frame? Or a Seeley?

Post by Alan H »

I think I'd be looking at something more tunable than a 380, unless you have a Barton liquid cooled 500cc conversion on yours!
Think of how stupid the average person is, then realise that half of them are more stupid than that.
User avatar
johnu
On the main road
Posts: 156
Joined: Thu Sep 29, 2016 4:53 pm
Country: United States
Suzuki 2-Strokes: T500

Re: gt380 with a featherbed frame? Or a Seeley?

Post by johnu »

Zunspec4 wrote:
sportston wrote:So far a Dresda frame seems likely to offer best value for money, but it will be a long while before i can put my plan into action. Sniff sob
I have no clue as to the length of the waiting list for a Degens Dresda frame so order now and start saving :D

When you start with a virgin frame you have an open canvas to do what you want but a bunch of thinking/design/fabrication time to invest (and money)

There is a lot to do starting from this:
Image

Cheers Geoff
Nice Geoff :up: As far as frames go that would be a pretty easy one to build. I really will build my own frame one day. Done more than my fair share of brazing so would be a brazed frame and just clear coated 8)
What's your reason for using the 380, do you already have it?
Zunspec4
Expert racer
Posts: 1087
Joined: Tue Dec 16, 2008 11:37 am
Country: UK
Suzuki 2-Strokes: T500R, SV1000S, TS125, Seeley T500
Location: Trowbridge UK

Re: gt380 with a featherbed frame? Or a Seeley?

Post by Zunspec4 »

Hi John,

That is a photo of my Seeley T500 frame when I first got it. It is sportston who is contemplating a similar project but with a GT380 engine.

Here is a photo of my bike as it was last year.
Image

Cheers Geoff
User avatar
johnu
On the main road
Posts: 156
Joined: Thu Sep 29, 2016 4:53 pm
Country: United States
Suzuki 2-Strokes: T500

Re: gt380 with a featherbed frame? Or a Seeley?

Post by johnu »

Lovely Geoff :clap:
Post Reply