Jump to content

+4mm Stroker Crank (long Rod)


Recommended Posts

I am fixing to order a stroker crank for my 01 banshee. But I have heard a bunch of good and bad about them. Here are my issues

 

#1 Do these cranks last long?

#2 Do they wear bearings and bores out quicker then a stock crank?

#3 Anything else wrong with them?

 

Thanks,

Kevin

Link to comment
Share on other sites

  • Replies 39
  • Created
  • Last Reply

Top Posters In This Topic

The wiseco cranks have what appears to be the same quality bearings as a standard crank. It should last just as long.

 

If you use a standard length rod I guess it may wear the bore out faster in theory. Dan at patriot doesn't think it needs to have long rods until it a 7mil stroker. You are only changing the stroke each way by 2mm. I don't think that's enough to wear the bore noticably faster. If you by a wiseco crank it will have longer rods on it and may actually increase the life of the bore.

 

They say you may loose some top end with strokers if the rods are to long. Stroke is suppose to add bottom end. But, if you have it properly ported, pipes and use the proper carbs, you will be flyin.

 

I am not an engine builder but this is what I have read and been told. Take it as you will. If someone has a different opinion please post it.

Link to comment
Share on other sites

The wiseco cranks have what appears to be the same quality bearings as a standard crank. It should last just as long.

 

If you use a standard length rod I guess it may wear the bore out faster in theory. Dan at patriot doesn't think it needs to have long rods until it a 7mil stroker. You are only changing the stroke each way by 2mm. I don't think that's enough to wear the bore noticably faster. If you by a wiseco crank it will have longer rods on it and may actually increase the life of the bore.

 

They say you may loose some top end with strokers if the rods are to long. Stroke is suppose to add bottom end. But, if you have it properly ported, pipes and use the proper carbs, you will be flyin.

 

I am not an engine builder but this is what I have read and been told. Take it as you will. If someone has a different opinion please post it.

I think you forgot to add Rod, that your bike flat out fuckin flys. :headbang:

Link to comment
Share on other sites

I went on the dyno yesterday, but only got one run in since my clutch would slip after 7000rpms....I have less bottom end then before even w/ the 30mm carbs...I just put a new clutch in and will be doing a lot more dynoing w/ the 4mil stroker...I'll update later this week...

Link to comment
Share on other sites

I went on the dyno yesterday, but only got one run in since my clutch would slip after 7000rpms....I have less bottom end then before even w/ the 30mm carbs...I just put a new clutch in and will be doing a lot more dynoing w/ the 4mil stroker...I'll update later this week...

What porting style, stroke compensation, and crank did you go with?....Jim

Link to comment
Share on other sites

I have a torque or low end porting, Hot Rod crank, decked the cylinder, and put a spacer plate between the head and cylinders. The transfers were done, it was case matched, I'm running a +4 timing, and 165psi...Also have the long rod....Its going on the dyno tomorrow eve. I'll know more then, I'll be testing some ported stock reed cages, 30mm carbs, and if I have time, the stock and 33mm carbs. What are you thinking Jim?? My builder thought I'd turn less rpms and have more torque, but less hp......From what I've seen and ridden so far, it has less bottom end, but a shit load of more hp and torque at a higher rpm......Not sure if my stock reed cages are holding me back......we'll see tomorrow....

Link to comment
Share on other sites

Banchetta, in the term "decking the cylinder" are you referring to lowering the cylinder itself or just referring to the spacer on the top? Although the options are endless in setting up a +4, it has been my experience that they love transfer duration and if you give it enough of it, you can go with some pretty wild exhaust durations as well and still have killer bottom end and only give up a few hundred rpm on the big end compared to a heavily ported 350 crank motor.. Even with the loss of peak rpm, the motor will still pull much harder and longer even with tall gears so your top-end speed is still WAY improved over a radical ported 350 crank and still have killer bottom end.

If your goal was low -end, and I'm just assuming that it is, it might be that your engine is wanting more transfer duration depending on how you "decked" it. If you give it enough transfer duration, 200 degrees ex. duration is not excessive and still have major grunt...Jim

Link to comment
Share on other sites

The wiseco cranks have what appears to be the same quality bearings as a standard crank. It should last just as long.

 

If you use a standard length rod I guess it may wear the bore out faster in theory. Dan at patriot doesn't think it needs to have long rods until it a 7mil stroker. You are only changing the stroke each way by 2mm. I don't think that's enough to wear the bore noticably faster. If you by a wiseco crank it will have longer rods on it and may actually increase the life of the bore.

 

They say you may loose some top end with strokers if the rods are to long. Stroke is suppose to add bottom end. But, if you have it properly ported, pipes and use the proper carbs, you will be flyin.

 

I am not an engine builder but this is what I have read and been told. Take it as you will. If someone has a different opinion please post it.

I think you forgot to add Rod, that your bike flat out fuckin flys. :headbang:

in laymens terms ill go with that stan..........i know my stock bore after 40 brutal hours with some bolt on stuff had 135 psi in one jug and 110 in the other, but the crank was pristien....but my passion motor has closer to 60 hours on it and still has 180 psi in both jugs, i check it every few weeks for shits and grins and its holding up great, i dont know if its cause you cant ride it as hard and hang on, or its winter and the 40 hours on my stock bore was in summer at about 90 degrees and my passion motor hasnt seen 70 degrees yet, you can pound a stock bore with short gears, but geared tall with some ponies you tend to be at way less rpm's to cover as much ground....... the aftermarket crank and pistons have to be every bit as good as the stockers youd think?.......Banchetta glad to hear you stroked your bike, still running the turner pipe?, im eager to see how the dyno was, why not try pj34's, the 34's and deltas are a good combo, i think i feel a harder pull from say about 4000 rpm to 8000, than i do from 7500 on up im not sure if its cause my pipes cant pull that volume like they can on the lower side or its just the way jims motor runs, please post how your bike dynos, i have buddys with lowend ports that say they same thing about mid to top pull that you did, trinity mx ports act like that...... i think with jims motor he does a combo of things that work well together, maybe his intake with the deltas and pj's along with his 12 port do it, pipes dont seem to make that big a difference, air flow does though, not a set up for a cut stock lid.......

Link to comment
Share on other sites

UPDATE:.....I tried the stock, 30mm carbs, and 33mm carbs and pulled the same exact hp and torque and the same exact curve to go w/ it..... :whoa: Go figure....Next, I lost a lot of low end torque between 3000-6000rpms and lost hp as well and now created a bad dip at 5500rpms...We're testing the reed spacers in both positions tomorrow to see if that'll take the dip out....So far, my peak torque curve only moved to a higher rpm w/ no gain, and the hp also moved higher w/ a 5hp gain...My curve pulls hard from 6000rpms to 8800....Jim, any ideas why I didn't gain any torque??? He might not have decked the cylinder (lowered it), it was mentioned when I brought the motor, but I don't think he did considering there is only a 2mm plate on top and he said I should have the same compression as before. I'm going to see him tomorrow to get some info....and see what he says....

Link to comment
Share on other sites

wow banchetta, doesnt sound good at all. i cant get over that the carbs didnt do a damn thing. i would think you should be seeing +15-20hp increase with that crank and porting, and way more torque. sorry but it doesnt sound right to me!

Link to comment
Share on other sites

UPDATE:.....I tried the stock, 30mm carbs, and 33mm carbs and pulled the same exact hp and torque and the same exact curve to go w/ it..... :whoa:  Go figure....Next, I lost a lot of low end torque between 3000-6000rpms and lost hp as well and now created a bad dip at 5500rpms...We're testing the reed spacers in both positions tomorrow to see if that'll take the dip out....So far, my peak torque curve only moved to a higher rpm w/ no gain, and the hp also moved higher w/ a 5hp gain...My curve pulls hard from 6000rpms to 8800....Jim, any ideas why I didn't gain any torque??? He might not have decked the cylinder (lowered it), it was mentioned when I brought the motor, but I don't think he did considering there is only a 2mm plate on top and he said I should have the same compression as before. I'm going to see him tomorrow to get some info....and see what he says....

Your probably going to notice more gains with the bigger carbs on mid to high rpm in the dirt more than on the dyno. The load factor is going to make a big difference on how well those bigger carbs are feeding the intakes unless ofcourse the intakes are near stock in size. Torque is something I havn't had trouble in getting out of +4's, but my set-up is completely different than what your running. Did you get my last post?...your lack of torque is almost certainly port timing...Jim

Link to comment
Share on other sites

Update: I talked to my builder, he ported it w/ 35 degrees blowdown, widened the exhaust w/ slight raise, 196 degrees exhaust, and 116 degrees intake...What does this mean to you Jim? He also put 1/4" booster ports on each side of the intake by the reeds.....

Next, we went to the dyno w/ v-force reeds and prodesign intake and tried those.......Walla!!!!!! We gained 5hp and 4lbs of torque w/ stock carbs....The ported stock cages gained 2hp, and the v-force w/ intakes gained 5 more over the ported stock....WE then went to 35mmPWK carbs and tried them. Gained another 2hp and 2 more lbs of torque.......Now we're talking...The shee is pulling 63hp now w/ 41lbs of torque @8200rpms....The stock carbs pulled nicely, but the 35's pulled extremely harder (about 4-5hp) between 1-6000rpms, then stayed the same until 7500rpms and pulled harder by 2hp on top......So much for the theory of larger carbs have no low end....... <_< I'm happier w/ my motor now, but I still have a nasty dip at 5500 rpms....any ideas???

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...

×
×
  • Create New...