FireHead Posted March 26, 2007 Report Share Posted March 26, 2007 From what I gather over on Planet Sand the triple cylinder engine class breaks down like this for most tracks around the Oregon area: 3 Cylinder Class ------------------------------ 1. 1325cc and Up 2. 0-1324cc The question is: What are the advantages and disadvantages of being in either of the two displacement classes and why? I would ask this question over on PS, but there are alot of twats over there that buy all of their stuff as opposed to build and tend to not know what they are talking about or distort the truth to make themselves feel better. I would just assume not have to read through all that to be able to get good information from the few industry folks that are over there. Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 26, 2007 Report Share Posted March 26, 2007 "tipically" the bigger tripples are on laydown chassis'.. the "smaller" tripples (if theres a such thing..lol) are normally the banshee style ones in the atv type chassis.. right now there are a few 18mm tripple dm's out there that would be in the 0-1324cc class with you.. Quote Link to comment Share on other sites More sharing options...
FireHead Posted March 26, 2007 Author Report Share Posted March 26, 2007 "tipically" the bigger tripples are on laydown chassis'.. the "smaller" tripples (if theres a such thing..lol) are normally the banshee style ones in the atv type chassis.. right now there are a few 18mm tripple dm's out there that would be in the 0-1324cc class with you.. Would you think I would be at a disadvantage in the 1325cc and up class if I was on a Banshee style suspended frame? I would think that I should eventually be able to make as much power as a 18mm DM cylinder triple engine. My frame might not wind up being the greatest ever for a pure drag application. I guess my main concern is if a laydown trike with triple snowmobile engine is going to walk all over me no matter what I do? Are the showing on a given race weekend pretty small in the triple classes or are there alot of folks that show up with triples? Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 26, 2007 Report Share Posted March 26, 2007 at local races tripples arent too common but they are out there and do show up from time to time.. the laydowns are hitting awsome times, but with a well designed rigid upright chassis you should be able to run with them (given the power output is around the same..)..the huge twins are running with them now as well.. cc's of the motor may help with the classing, but a smaller motor may run harder with a better set up and tune than a bigger motor with a half assed set up..so that would be another point to consider as well. in a suspended chassis your adding weight back that you already didnt want to have with just the suspension components (even if its strutted, there is still weight there that you dont really want) on a given race day though you may end up being the only or one of two tripples at your track (depending on the area). so your class may not be as big as you would like to see.. either way its still interesting to see one run and run well.. what sort of tripple are considering building? imo i would look into the banshee cased style tripple more than the sno-mo stlye, because i would rather that type of set up.. that is all personal opinion though.. Quote Link to comment Share on other sites More sharing options...
Ruko Posted March 27, 2007 Report Share Posted March 27, 2007 I would think that I should eventually be able to make as much power as a 18mm DM cylinder triple engine. Sry I don't know much about triples, and this is unrelated to your topic, but what do you guys mean when you say "DM"? Quote Link to comment Share on other sites More sharing options...
Malott 1 Posted March 27, 2007 Report Share Posted March 27, 2007 Sry I don't know much about triples, and this is unrelated to your topic, but what do you guys mean when you say "DM"? It's a different cast cheetah. I think they have cr500 intakes and huge bores. There is a pic of one over on planet sand down in members rides. Quote Link to comment Share on other sites More sharing options...
FireHead Posted March 27, 2007 Author Report Share Posted March 27, 2007 at local races tripples arent too common but they are out there and do show up from time to time.. the laydowns are hitting awsome times, but with a well designed rigid upright chassis you should be able to run with them (given the power output is around the same..)..the huge twins are running with them now as well.. cc's of the motor may help with the classing, but a smaller motor may run harder with a better set up and tune than a bigger motor with a half assed set up..so that would be another point to consider as well. in a suspended chassis your adding weight back that you already didnt want to have with just the suspension components (even if its strutted, there is still weight there that you dont really want) on a given race day though you may end up being the only or one of two tripples at your track (depending on the area). so your class may not be as big as you would like to see.. either way its still interesting to see one run and run well.. what sort of tripple are considering building? imo i would look into the banshee cased style tripple more than the sno-mo stlye, because i would rather that type of set up.. that is all personal opinion though.. My chassis is going to be a suspended hill shooter style chassis. By the time I try to race my new engine it will be tuned pretty well, but the sorting the chassis tune out may be a whole other story. I am going to certainly keep the weight down through out the entire bike. Currently the engine as designed, with it's pipes, weighs less than an OEM Banshee engine. My triple is some what of a custom deal. Most parts are Banshee'ish, but I am making most of the parts my self. Tthe cases, the cylinder block, the crank, rods, some of the transmission and drive components are all parts that I am making. My challenge at the momement is that I need to bore my sleeves and get my pistons ordered before I change jobs, hence why I have to finally sort out the displacement. The upside of going smaller with the engine is that I can push the rpm envelope up a bit. I think I am leaning towards going 1324cc or smaller at the moment. :geek: I personally do not like the snowmo based triples. A crankenstein motor is one thing, but the snowmo engine grafted into a Banshee frame looks kind of gay to me. Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 27, 2007 Report Share Posted March 27, 2007 malott1 is right on.. ill take a pic of my dm's tomorrow when i get back where they are.. the smaller cheetah's are 73 and 74.5mm bores, and the dm's are 78mm bores.. the dm's were started for the big stroke monsters but now there are some that are coming out for the 4-10mm strokes as well.. different port layout but 78mm bores.. there is ALOT of case work to be done in order to make the dm's fit on the stock cases!! Quote Link to comment Share on other sites More sharing options...
FireHead Posted March 27, 2007 Author Report Share Posted March 27, 2007 Sry I don't know much about triples, and this is unrelated to your topic, but what do you guys mean when you say "DM"? A DM is the "new" Cheetah cylinder. :thumbsup: Quote Link to comment Share on other sites More sharing options...
Ruko Posted March 27, 2007 Report Share Posted March 27, 2007 A DM is the "new" Cheetah cylinder. :thumbsup: cool thx... I guess they'll allways find a way to get bigger :biggrin: Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 27, 2007 Report Share Posted March 27, 2007 firehead: good luck with the build of your motor.. i deffinitly wish i had the ability to make my own trans and such.. maybe you could build the next billet trans with a 1-5 or 1-6 for the asphalt guys.. i forgot to add earlier that "DM" stands for dominant male as well.. Quote Link to comment Share on other sites More sharing options...
FireHead Posted March 27, 2007 Author Report Share Posted March 27, 2007 firehead: good luck with the build of your motor.. i deffinitly wish i had the ability to make my own trans and such.. maybe you could build the next billet trans with a 1-5 or 1-6 for the asphalt guys..i forgot to add earlier that "DM" stands for dominant male as well.. I didn't mention the definition of DM because I think it's kind of gay. :laugh: I am only making some of the transmission parts (main drive gears, shift forks, etc.) The stock transmission parts are being re-heat treated and the gears nitrocaburized at the moment. I gun drilled all of the transmission shafts and did a bit of "override" style work to the gears and shift drum before I sent the parts out to heat. All of the shaft bearings in the motor are going to be larger and a different style than OEM. At some point, I am going to have to sort out the chain size I am going to run. All the math to do that seems to get kind of fuzzy on the upper end of the chain market. Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 27, 2007 Report Share Posted March 27, 2007 (edited) yeah i know what you mean about the name of the cylinders..lol, but hey i would call them grilled cheese as long as they run hard..lol billet shift forks?? hmm.. that sounds pretty interesting there.. the chain should be easy.. i would deffinitly go to the 530 chain, they are a little heavier than the 520's but by the time you pay for two 520's you could have bought all the different size sprockets and one chain for the 530.. (the 530 is what i am going to be running as well) the front sprockets are 25 each, the rears aroun about 65 or so each.. the chains are made to stand up to street bike powers for the oem chains and the good aftermarket chains are good enough for the 500+ hp busa's so i think im not going to be breaking this chain.. Edited March 27, 2007 by lowriderb Quote Link to comment Share on other sites More sharing options...
FireHead Posted March 27, 2007 Author Report Share Posted March 27, 2007 billet shift forks?? hmm.. that sounds pretty interesting there..the chain should be easy.. i would deffinitly go to the 530 chain, they are a little heavier than the 520's but by the time you pay for two 520's you could have bought all the different size sprockets and one chain for the 530.. (the 530 is what i am going to be running as well) the front sprockets are 25 each, the rears aroun about 65 or so each.. the chains are made to stand up to street bike powers for the oem chains and the good aftermarket chains are good enough for the 500+ hp busa's so i think im not going to be breaking this chain.. I am doing the billet shift forks for two reasons, the first being I want to put proper bearing in the fork fingers (hopefully better than an RZ250 shift fork). The second is that I belive the override modifications I made to the transmission will ingrease the bending load on the forks, so I designed the forks a little differently. Yeah, I have been looking at running a 530 series chain as well. My real problem is that I cannot get my chain strength calculations to match the chain manufacturers advertised tensile strength (DID ATV X-Ring for example). Via the simulation work that I have done so far, a heavier chain does not seem to take away much from the engine like you might think it would via a heavier rotating mass. I am not worried about breaking a chain if I buy one that is within in the specifications of my engines output. I am worried about a larger chain binding under hard accelleration. I think that could be resolved by reposition in a cahin guide or two. :geek: Quote Link to comment Share on other sites More sharing options...
lowriderb Posted March 27, 2007 Report Share Posted March 27, 2007 (edited) i dont think the bigger chain will bind under too much of a load, especially if your going to be running 15 tooth and up sprockets.. having rollers on the shift forks could help, but the better design to prevent them from bending is what i would be interested in for sure..lemme know if you want a guinea pig for them :biggrin: ive seen the shift drum be force out of the cases (clutch side) on just 14mm strokes so im really ganna have to watch this big motor with doing that closely.. Edited March 27, 2007 by lowriderb Quote Link to comment Share on other sites More sharing options...
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