Barrel Question GT/TT250

[markm]

Hi everyone, I'm sure this subject goes round and round from time to time but wanted to know if barrels from a GT250 A/B/C with part numbers 11210-18600 & 11220-18600 would fit on a '72 GT/TT250 that best I can tell uses 11210-18400 & 11220-18400?
From what I have read ports are different...Would they be worth a punt or hold out for the correct ones for the year of the bike?

[markush]

Hi!
Cylinders are not interchangeable between GT250K/L/M and GT250A/B/C due to different stud spacings on inlet side.

http://suzuki-gt250.de/motornavi/motor.php?b=2

http://www.oldjapanesebikes.com/mraxl_G ... /index.php

Markus

[markm]

Thanks Markus
I guessed as much. From what I've read interchangeability is a nightmare on the mid 70's stuff. Thought I might be lucky going onto an earlier bike though.
Cheers
Mark

[markm]

Okay so trawling ebay and see 11210-18100 and 11220-18100 pop up from time to time. Look like they were listed as fitment on '72 250R etc. There was a thread a while back about exhaust port differences.....? Anyone know if early cylinder barrels could be a good substitute to 11210-18400 and 11220-18400. would there be any compatability or performance issues? Thanks all

[Vintageman]

The 76 and up gt250 exhasut port if I recall is 29.5 mm like Rd350. The 76 and up gt250 It has extra boost ports. also 28mm carbs versus 26mm That bike is actually tuned fairly hot!

As far as the T/GT250 cylinders I think they were all ported the same (+/- 1/2mm)and advertise 30-33 or so hp. If you don't need cylinders i don't think you will gain. I mm off exhaust port height makes a huge difference street The are like 32.5mm - 32MM OEM EX height stock.

Here is set that look like very interesting if you want performance .

http://www.ebay.com/itm/SUZUKI-T250-SUZ ... xyYYlRr2DG" onclick="window.open(this.href);return false;
http://www.ebay.com/itm/T250-SUZUKI-69- ... xyu4dRr1-b" onclick="window.open(this.href);return false;


someone spent some significant effort doing that porting job one those cyls... someone buy them or I just may. .. and i don't even have T/GT250 maybe too radical... maybe not?

It think you can run the t250 head if you don't like the GT250 RAM Air look

[markm]

Thanks vintageman yes I saw those also. What I am trying to find out is if early T250 hustler barrels / jugs will run okay on my '72 TT 250. I plan to build a stock motor and have a set of NOS standard first size pistons. Idea was to find some NOS barrels for the fresh motor. When I look down the exhaust my old barrels have two extra ports either side but the older hustler port is just one large one?
First restoration project and hoping for some advice

[Vintageman]

I am not sure what a 72 TT250 is? Don't think that model in usa. I thought all cylinder from T250 - 75 GT250 fit.

The one without extra EX port is older so I am not 100% sure same family. If no one knows I would look up the base gasket # and if interchangeable it most likely fits. Verify same stroke and bore . I know the 68 T305 and 69 T350 had only one EX port and Circa 1970 the T350 had those extra little ports ... which I think are just a gimmick (to compare against Yam for example) for they made the large port smaller to accommodate the two little ones. The two little ones plug with carbon easy and should be polished.

[markm]

Good point about carbon build up on the smaller ports, seems to make sense. I have the original barrels and some plus one millimetre NOS pistons too, but thought it would be neat to build the motor with first size as I do want to ride the thing for a while.
Mine is the model in between the hustler and the first GT with disc brake. So it still has the drum brake up front. It looks a lot like the 350 Of the same year.