DT25 '96 model - can i convert it to a 30 ?

[quietstorm]

Hi all,<br /><br />Just picked up an oil injected DT25 '96 model - being a 3 cylinder i figure that it's a detuned 30 (or higher).<br /><br />what is required to convert it from a 25 to extract the additional hp.<br /><br />many thanks,<br />storm.

 

[WillyBWright]

Re: DT25 '96 model - can i convert it to a 30 ?

Best and most economical way is almost always to trade the 25 in on a 30.

 

[rodbolt]

Re: DT25 '96 model - can i convert it to a 30 ?

cheapest way is to change the decals. maybe Fridays marine can help. very knowledgable folks there. post another message to Fridays marine attention.

 

[classic 24]

Re: DT25 '96 model - can i convert it to a 30 ?

the only difference between the DT25 and the DT30 are the carbs.

 

[WillyBWright]

Re: DT25 '96 model - can i convert it to a 30 ?

Is that based on Fact, or what you've heard? I want to see part numbers. In modern 2-strokes there are usually a number of differences, the carb being just one.

 

[classic 24]

Re: DT25 '96 model - can i convert it to a 30 ?

it is a fact! I have been working on Suzukis for 13 years. 25/30 different carbs. 55/65 different carbs. 75/85 different carbs. etc. etc,

 

[jleus]

Re: DT25 '96 model - can i convert it to a 30 ?

Interesting info about the carbs. They do have different part numbers but the sets of each measure the same in venturi diameter for me. Jetting is somewhat different. The biggest thing is the "throttle interlink" is stopped short on the 25. The plastic can be ground down so the throttle turns through to fully open throttle. I did that on mine many years ago and decided to order the 30 interlink and it seems it is perpetually back ordered through my usual source......you got one classic 24?....just the motor side of the interlink. <br /><br /> http://www.brownspoint.com/?src=overture <br /><br />good resource for downloadable parts "blowups" and pretty good pricing and service. <br /><br />Not saying your wrong but the carbs are NOT the only difference, in my experience the carbs are no difference, the 25 is stopped short....look down the throuts of the carbs, you'll see.<br /><br />I'm talking about the C models, the three cylinders.

 

[rodbolt]

Re: DT25 '96 model - can i convert it to a 30 ?

are the exhaust pipes all the same? seems I remember the 75 and the 85 had different adapters as well

 

[jleus]

Re: DT25 '96 model - can i convert it to a 30 ?

I understand there is a long and a short exhaust tube. The part numbers support that. Mine was short and is now a little shorter (per a local dealer's sons instructions) but I don't think I got much out of that. I believe the 30 head is tighter also. There was a design change in the head in about '91 '92 that made the plug more in line with the bore but gave the head more volume. I found an '89 30 horse head that was pre-change that really picked mine up. I cc'ed each and the earlier 30 head was on average 1.6 cc less volume than the post change 25 head across the three holes. To identify heads there is a 25 or 30 cast in the starboard side near the top. Plug angle indicates vintage. I have not compared same design 25 and 30 horse heads.

 

[fridays]

Re: DT25 '96 model - can i convert it to a 30 ?

Listen to Classic 24..it's the carbs and to be more precise it's just the linkage that only allows your 25 to open up about 2/3 of the way. Same body, same jets (usually..depends on year), same everything except linkage and decals.

 

[fridays]

Re: DT25 '96 model - can i convert it to a 30 ?

jleus is also right about different years where there were changes in the head etc. but within the same year carbs were it.

 

[jleus]

Re: DT25 '96 model - can i convert it to a 30 ?

Not splitting hairs Fridays but you agree that it is NOT different carbs as decribed above.....it IS mostly that inboard piece of the throttle interlink. I understand you have been in the Zuki biz for a while.....do you have a 30 horse motor side interlink piece (part# 19122-87D00)?.. my ground off 25 works but looks rough. My normal source has me on back order. <br /><br />If anyone wants to play with jetting in these things my experience is the jets can open up some when you get the throttle open. 120 jets are 1.2 mm 125 is 1.25 mm and so on. The jets from the factory don't agree well with the same size wire drill bit (my experience). My 120s were notably smaller than the 1.2 mm bit (micrometer verified on the solid part of the bit) I took to them. I have done some other things to get her to breath, she seems to like it best rich enough to just wash the carbon from the intake side of the piston top. Pulls hard to 5800+ rpm and is very smooth in that range.

 

[fridays]

Re: DT25 '96 model - can i convert it to a 30 ?

jleus...I do have your interlink piece used. Call me next week..804-758-4131.. and I'll send you one.