VinceDizzy Posted August 6, 2005 Report Share Posted August 6, 2005 Im deciding to build another bike this winter with a Cub. Are there any advantages or dissadvantages to running a 7mm crank instead of a 4mm? I see many on this site run 4mm? Any info would be appreciated. Quote Link to comment Share on other sites More sharing options...
wesw Posted August 6, 2005 Report Share Posted August 6, 2005 7mm you have the trench the cases for the crank i think thats what they call it. 4mm are basically drop in and go with some cut domes Quote Link to comment Share on other sites More sharing options...
racer Posted August 6, 2005 Report Share Posted August 6, 2005 yup trenching is required. it also costs a lil more for the bigger crank, but not enough to be a deciding factor. youll probably get more power from a 7mm, but i think thats the only plus. Quote Link to comment Share on other sites More sharing options...
locogato11283 Posted August 6, 2005 Report Share Posted August 6, 2005 7mm you have the trench the cases for the crank i think thats what they call it. 4mm are basically drop in and go with some cut domes 401711[/snapback] yea cases have to be trenched..i think most places charge around 100 bucks to do it. yup trenching is required. it also costs a lil more for the bigger crank, but not enough to be a deciding factor. youll probably get more power from a 7mm, but i think thats the only plus. 401723[/snapback] arent the 7mm cranks quite a bit more expensive than the 4mm? a lot of people on PS say why go 7mm when you can go 10mm for the same price...and i have heard the 10mm cranks are up around 1000 bucks. 600 bucks could be a deciding factor for sure... Quote Link to comment Share on other sites More sharing options...
switchblade Posted August 6, 2005 Report Share Posted August 6, 2005 I thought you didn't have to trench case until you got to a 10 mm Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 6, 2005 Report Share Posted August 6, 2005 yea cases have to be trenched..i think most places charge around 100 bucks to do it.arent the 7mm cranks quite a bit more expensive than the 4mm? a lot of people on PS say why go 7mm when you can go 10mm for the same price...and i have heard the 10mm cranks are up around 1000 bucks. 600 bucks could be a deciding factor for sure... 401737[/snapback] Yea the 7mil and 10mil cranks are exact same price, right at a grand. I also didn't know cases needed trenched until you hit 10mil? Only disadvantage I can find for the 7mil is the price. Quote Link to comment Share on other sites More sharing options...
Big Blue Posted August 6, 2005 Report Share Posted August 6, 2005 anything over 4mm requires the cases to be trenched and the cost of the crank is alot more than a 4mm. http://www.twistercrankshaft.com/cranks.htm Quote Link to comment Share on other sites More sharing options...
rocketboy Posted August 6, 2005 Report Share Posted August 6, 2005 Yea the 7mil and 10mil cranks are exact same price, right at a grand. I also didn't know cases needed trenched until you hit 10mil? Only disadvantage I can find for the 7mil is the price. 401752[/snapback] yep anything over 4 millimeters requires trenching the cases. the price for the 7 and 10 starts to add up quick on these more exotic type builds ,and as we all know the best bang for the buck is a dune/drag ported 4 mill. i would be inclined to belive if your going to go for a 7 or a 10 mill stroker consider either buying a used engine already setup for one or running a ported cub 4mm which im sure is equal to stock ported jugs with a +7 mm stroke Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 6, 2005 Report Share Posted August 6, 2005 yep anything over 4 millimeters requires trenching the cases. the price for the 7 and 10 starts to add up quick on these more exotic type builds ,and as we all know the best bang for the buck is a dune/drag ported 4 mill. i would be inclined to belive if your going to go for a 7 or a 10 mill stroker consider either buying a used engine already setup for one or running a ported cub 4mm which im sure is equal to stock ported jugs with a +7 mm stroke 401762[/snapback] I think I'll stick with the 4mil. Now whether to go 65 or 68mm bore? Man all these decision. Gotta love it. Quote Link to comment Share on other sites More sharing options...
Big Blue Posted August 6, 2005 Report Share Posted August 6, 2005 Go with the 65 im curious to see what the power differences may be or which ever one you will be able to get sooner. Quote Link to comment Share on other sites More sharing options...
racer Posted August 6, 2005 Report Share Posted August 6, 2005 i think im thinking of 4mm/stock stroke being pretty comparable. Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 6, 2005 Report Share Posted August 6, 2005 Go with the 65 im curious to see what the power differences may be or which ever one you will be able to get sooner. 401769[/snapback] I foujnd 2 places that have the 4mil in stock right now. I'll post who after I order it. BB why you say the 65mm? Quote Link to comment Share on other sites More sharing options...
Big Blue Posted August 7, 2005 Report Share Posted August 7, 2005 That way ill have a slight advantage at the hq trip Not really, I dont see many people talking about having the 65 everyone seems to go with the 68 on the 4mm's, so where are you looking to get one from? Quote Link to comment Share on other sites More sharing options...
VinceDizzy Posted August 7, 2005 Author Report Share Posted August 7, 2005 (edited) Great info Thanks Edited August 7, 2005 by VinceDizzy Quote Link to comment Share on other sites More sharing options...
RNBRAD Posted August 7, 2005 Report Share Posted August 7, 2005 That way ill have a slight advantage at the hq trip Not really, I dont see many people talking about having the 65 everyone seems to go with the 68 on the 4mm's, so where are you looking to get one from? 401836[/snapback] Cascade Innovations if I have problems getting them from the builders. Quote Link to comment Share on other sites More sharing options...
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