Engine Rebuild

General discussion about Street two-stroke Suzuki motorcycles.

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Doss1961
On the street
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Joined: Mon Dec 11, 2017 3:19 pm
Country: United Kingdom
Suzuki 2-Strokes: T250 Hustler

Engine Rebuild

Post by Doss1961 »

I'm about to start my rebuild of my T250 engine and I'm wondering if anyone knows the torque settings and sequence for the top and bottom engine casings.

Thanks
Paul
dollydog
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Suzuki 2-Strokes: several gt250 ramairs

Re: Engine Rebuild

Post by dollydog »

hi paul, there should be numbers cast into the crankcases which shows you the sequence to undo and redo all the bolts. i always take the top 4 bolts out last and replace them first. but be careful with all the m6 bolts as they are very easy to shear - they are getting on 50 years old don't forget. i always replace them with new stainless hex head bolts and copper grease them. can't find the torque settings at the mo, but it's pretty low :D if i find it, i'll post it up. if you can't find the numbers, they are just undone in as diagonal a sequence as you can manage, like top right, bottom left etc.
cheers, dd.
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Craig380
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Re: Engine Rebuild

Post by Craig380 »

As Dolly says, the bolt holes have numbers near them to indicate the sequence. Suzuki's recommended specs for the crankcase bolts (which should all have the letter S on their heads) are:

6mm bolts: 5 to 7 lb-ft
8mm bolts: 10 to 17 lb-ft
10mm bolts: 18 to 29 lb-ft

(the measurement indicates the shank diameter, not the bolt head size)
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jabcb
Moto GP
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Suzuki 2-Strokes: 69 T350 thru 75 GT750
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Re: Engine Rebuild

Post by jabcb »

The T250/T350 was based on the T305, which was based on the T20.
The T250/T350 shop manual is pretty skimpy on info. Some additional info is in the T305 manual & T20 manual.

The T500 crankcase bolt tightening order is on page 45 of the T500 shop manual.
I think later T500s have an additional bolt, so this isn’t exactly correct for the later motors.
The T500 bolt order should be a pretty good guide for your T250.

Shop manuals are here: https://www.oldjapanesebikes.com/mraxl_ ... /index.php
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