OzVMX Forum
Clubroom => Tech Talk => Topic started by: TT5 Matt on May 25, 2016, 08:04:44 am
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has any one got a list of rod kit dimmensions they could put a link up for? i saw one back in 2012 which i could scroll down the list to match up a rod for my ts185a project bike which i found back then but ive since misplaced the little book i put the details in. yeah i know all the 185 specs but im after a rod to match a 18mm piston pin instead of 16mm
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Hmmm what piston ?
For stock size pins if its of any use try 6mm barrel spacer and rd350 rod. Also suits some larger snowmobile pistons .
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There are dimensions listed in a couple of the parts catalogues I have so if you post the dimensions of the TS rod I will take a look.
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ok crank pin is 22mm/rod centres are 110mm/piston pin 18mm/big end width 17mm/small end width 23.8 mm but can be more.the rod i found to suit before was from a odd ball make ive never heard of maybe out of a european country.what i want to do is stuff a pe/rm250B piston into my ts185A using the stock 22mm crank pin size,i know it can be done but the fellow who did it didnt want to tell me.Pokey theres plenty of 185 rod kits around and dt200 kits are the same size as well but theres no oil gallery if you want to use the oil pump which also feeds the big end like a 4t does.
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I thought they were
130 16 21 width 17
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Try mitaka.co.uk the one that may fit is an early Maico 250 rod according to their site but you may need a spacer under the cylinder.
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the 110mm stock Suzuki rods are available everywhere as well as plenty of 110mm with 16mm ID small end bearing rods such as the Banshee and RD rods, thats not the issue here. We are looking for 110mm long with that takes a 18mm gudgeon pin. I have found plenty of Polaris 112mm rods but they take a 24mm big end pin which is no good if you want to keep the hollow oil feed design of the stock 22mm pin. there may be a possibility to use the 112mm rods if a big end bearing can be found that will suit the polaris big end rod ID but have a 22mm ID bearing and suit the TS big end pin rather than the 24mm pin. That i still need to look into. Ideally it would be good to find that rod that TT5Matt said he found a number of years ago though.
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Yamaha 25HP twin (6GO) outboard is the only thing I can see but it is 18mm wide at both ends. 110mm centres 22mm small end and a 22x53 pin. Wouldn't be hard to machine a bit out of the wheels to suit. Wouldn't have a clue where to get one though.
Other thing would be the a 16mm pin rod kit and then sleeve the piston.
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thanks sleepy for the info,a long search on ebay found a yam 6go rod. id sooner machine a tad out of the crank halves for the trust washers then use a 16mm pin with sleeves.do you have the small end size in the rod so i can make sure i can get the right width bearing to match the piston?
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Would this be it?
http://www.ebay.com/itm/Pro-X-Connecting-Rod-Kit-Yamaha-OB-25-H-P-6GO-2528-/400985561643?hash=item5d5c9a1a2b:g:aB0AAOSwu4BV3fyR&vxp=mtr
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thanks sleepy for the info,a long search on ebay found a yam 6go rod. id sooner machine a tad out of the crank halves for the trust washers then use a 16mm pin with sleeves.do you have the small end size in the rod so i can make sure i can get the right width bearing to match the piston?
As far as I can see the small end is 18mm wide and 22mm ID. The bearing width is more related to the width of the piston boses, IE should be about .5mm narrower.
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http://www.mitaka.co.uk/MDP.htm
http://www.pro-x.com/prox-connecting-rod-dimensions-brand/
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Would this be it?
http://www.ebay.com/itm/Pro-X-Connecting-Rod-Kit-Yamaha-OB-25-H-P-6GO-2528-/400985561643?hash=item5d5c9a1a2b:g:aB0AAOSwu4BV3fyR&vxp=mtr
Part numbers look correct but the photo doesn't
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Yeah i got the Pro-X technical catalogue with all the rods but couuld not find that outboard rod. Maybe their outboard stuff is in a separate catalogue to the bike/snow/PWC stuff :-\
Ebay pic is KTM rod by the look of it.
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thanks to sleepy and tomas for your input and links as im useless at finding things on the net.both the yam 6g0 rod and maico rod are usable with abit of work though im leaning to the longer 125 between centres maico rod providing the 15mm spacer under the barrel doesnt imped flow threw the transfers too much as the outside radius of the transfer ports will suffer.ill do a mock up using a dummy rod made out of alloy flat bar and a part spacer to see whever i can get the transfer radius right before i spend any money.i like the longer rod due to the piston spending more time at the top and bottom of the stroke allowing for more crankcase filling/exhaust scavengeing and cylinder filling as well as more torque/less piston acceleration,old tricks v8 engine builders use
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Good luck finding a reasonbly priced Maico rod. I would be a bit concered about the balance of the crank with the longer rod and the larger piston. Atleast with the Yamaha rod it would only be a heavier piston.
I assume you are getting the Maico rod dimensions from the Mitaka list where it lists the big end as 22mm. I hate to let you know that they actualy have a 25mm pin, the list is incorrect. I see there are a few incorrect sizes listed there, use that list with caution.
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This must be what they are calling a Maico 250 rod.
http://new.kiwav.com/it/connecting-rods/royal-rods-ro-8208-connecting-rod-for-maico250-detail
Never seen a Maico with that rod but it could be the old oval case motors.
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There are plenty of rods in the 120-125mm range but that seems to be too long i reckon.
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There are plenty of rods in the 120-125mm range but that seems to be too long i reckon.
I think the idea was to find a rod with a 22mm bigend pin and an 18mm small end pin
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Thats right, but for me personally i would rather stay as close to 110mm as possible. There might be the possibility to use a TS250 big end pin to retain the oil feed, otherwise i think the Polaris 112mm rod will work if a 22 x 32.3 OD big end bearing can be found. Probably unlikely though at that special OD. Well Hot Rods Polaris rod uses that odd OD, i have not checked Prox yet.
http://www.hotrodsproducts.com/ProductInfo.aspx?item_id=927
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yeah from what ive seen most 250's use a 125mm long rod/18mm piston pin's and 24/25mm crank pin's so ill just go with the easy to do and get yamaha 6g0 rod and use the suzuki crank pin to keep the bigend oiling system alive as it will be getting alot of rpm's, way higher then what mr suzuki ported it for!ill use a 250 oil pump to get abit more oil in the motor as well as thats not a bad thing and will help reduce the friction/heat.