1972 t250 conrods

[Chunkeydog]

Hi hope some one can help me with this one I am after 2 conrods part number 12161-18000 but can't seem to get my hands on any , I have been told that the gt 250 rods part number 12161-11000 will fit if I use the x7 pistons with the 14mm gudgeon pin rather than the standard pin size which is 16mm
Can any one confirm this for me
Cheers dean

[jabcb]

DiscountBikeSpares in the UK sells a complete kit with rods & pistons to do the upgrade.
The kit uses pattern parts made in Japan, so there might be a retailer on your side of the planet offering a better deal.

I don’t know if the kit actually works, maybe one of the forum experts can confirm that.

https://www.discountbikespares.co.uk/ou ... TTERN.html

[ConnerVT]

I don’t know if the kit actually works, maybe one of the forum experts can confirm that.

You do know, with 2500+ posts in this forum, you ARE one of the forum experts, right?

[Vintageman]

You can use the later rod with smaller eye for wrist pin. But, you really should NOT use the X7 piston with that kit (Changes inlet port timing to be much more radical.. loose bottom end.. ). However, you can use the GT380 piston or the later gt250 A/B piston. Same as the early one, but has the smaller wrist pin to fit that later rod.

FYI all my early 250s have been changed over to T350/305 and that larger piston requires the older rod with larger wrist pin diameter. If I had a 1976 and up GT250 I may leave as is for that thing is tuned for top end: smaller wrist pin less weight. But T350 has good power everywhere up to 7500 rpm. It has more torque at 400 rom than early t/gt250 has anywhere in its power band: Factory specs

From the guy with only 1293 posts

[Chunkeydog]

Thanks for the info much appreciated, I have a set of pistons I bought on ebay they claimed they were for a t250 but they had the 14mm gudgeon pin, so lucky I didn't send them back they are KHC part number 937520 they look the same as the original pistons but the skirt is about 5mm shorter
Any one know this brand.?, also checked my local suzuki dealer and they have 2 rods in stock couldn't believe it!,,
So hopefully will get it all back together over the next month
Cheers dean

[Vintageman]

5 mm shorter sounds like they are for the later X7 that was NOT sold in USA. 5mm is a lot, there is guy running these in gt380 seams OK for him (he might be ported on exhaust too?). But stock the 250 had a good middle of the road intake port timing that fit well with 7500 peak. shorter skirt increase the intake open time and under 6000 rpm I suspect you don't have much torque. I like longer intake timing, , but 5mm on that 250 is a lot IMO

Look for piston that fits GT380 or 76-78 Suz GT250 A/B/C. These have the smaller wrist pin and correct skirt lentgh. Many people in Europe confuse the gt250ABC piston for the GT250 X7... have them check skirt length

[jabcb]

eBay seller cruzinimage_co has pistons for the GT380 and GT250 for very reasonable prices.

My preference is NOS Suzuki, but other forum members have had good results with his pistons.
Just make sure to NOT select X7 pistons & look in the listing for 14mm piston pin size.

[Chunkeydog]

Thanks guys for the info much appreciated