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Author Topic: Big Bore for MX  (Read 913 times)

Offline JoePA

Big Bore for MX
« on: April 09, 2018, 07:37:33 PM »
I know this question has been asked a million times but how much difference in power between the 330 and 350 with similar port match from ESR. Is it worth going all out for the Big bore, say a 370 or will the smaller 330 get the job done? Whats the trade off? Is there a trade off?

Offline Tbone07

Re: Big Bore for MX
« Reply #1 on: April 09, 2018, 10:58:12 PM »
I'll just give you the reason I opted for my LED 350 over a smaller bore engine...

I'm around 240-245lbs and ride/race XC. Larger the engine the more torque, and as a heavier rider I need all the engine I can get. With the big-bore I can carry a higher gear and lug through sections of track without shifting as frequently. I can't see how having a larger engine would be harmful for XC or MX. I hear some guys say that large of an engine is too much to handle, but I think the opposite is true. It's not arm-ripping power, it's gobs of smooth controllable torque.

If I had to do it again I'd go even larger and get LED's stock stroke 370

« Last Edit: April 09, 2018, 10:59:56 PM by Tbone07 »
LED Performance 350 Sphynx - XC Machine
Laeger's-Roll-GThunder-HLS-PEP-HiPer-GBC

RIP Laz

Offline rablack21

Re: Big Bore for MX
« Reply #2 on: April 10, 2018, 09:23:17 AM »
For the small amount of money difference, the 350 is worth the extra. You still have to bore the cases and do all the same work. With that said, obviously the bigger the engine the more it will wear stuff out. With that said, 20cc is not a huge difference in the grand picture of wear/power/longevity. So then it comes back to money. As you move up in size, you will get more vibration though. My 310pv has noticeably less vibration than my 363. Just keep it in mind.

Online havinnoj

Re: Big Bore for MX
« Reply #3 on: April 10, 2018, 01:21:45 PM »
Agree with the comments on going for a bigger motor as long as itís setup for your needs.  More torque isnít going to hurt.  Vibration may be something you notice but at 350cc I never noticed much. 
« Last Edit: April 10, 2018, 01:35:02 PM by havinnoj »

Offline Burns363R

Re: Big Bore for MX
« Reply #4 on: April 10, 2018, 03:07:18 PM »
honestly i havent ridden a small bore 250r in so long i have forgotten what its like.  I dont feel like i have any vibration, but I would probably need to get back on a small bore and back that up.  Im probably just more used to it.

As far as hp and MX.  I dont think I would want my XC 370 for my MX bike, I think it woudl be to much.  The nice thing is Im not every at wide open on the XC bike, except for the straight aways.   On the MX track Im wide open alot more and that will really wear you out when your man handling that much power.   I know its backwards thinking but for XC its nice to have all that power in reserve and barley use the power in the woods.  Click up a gear and just modulate the throttle, smooth power!
TRX 363R 02- Laeger Narrow Frame/CR500 Link, Motowoz Suspension, Roll Design +4 LT Arms,RPM Dominator +4 axle, LED 363 MX, LED 350G Pipe, 38 A/S CR Ignition

TRX 363R 86- Stock frame(gusseted),KOQ-No Link Swinger, JD MGC LT Arms) Motowoz Shocks, LED 370/350D pipe, 38 A/S Carb, CR Ignition

Offline Tbone07

Re: Big Bore for MX
« Reply #5 on: April 11, 2018, 04:52:56 PM »
honestly i havent ridden a small bore 250r in so long i have forgotten what its like.  I dont feel like i have any vibration, but I would probably need to get back on a small bore and back that up.  Im probably just more used to it.

As far as hp and MX.  I dont think I would want my XC 370 for my MX bike, I think it woudl be to much.  The nice thing is Im not every at wide open on the XC bike, except for the straight aways.   On the MX track Im wide open alot more and that will really wear you out when your man handling that much power.   I know its backwards thinking but for XC its nice to have all that power in reserve and barley use the power in the woods.  Click up a gear and just modulate the throttle, smooth power!

How would you compare the difference in power between the +4 363 and stock stroke 370? Seems to me like they'd be pretty close
LED Performance 350 Sphynx - XC Machine
Laeger's-Roll-GThunder-HLS-PEP-HiPer-GBC

RIP Laz

Offline Burns363R

Re: Big Bore for MX
« Reply #6 on: April 12, 2018, 07:19:34 AM »
I feel the 370 has a much broader power band that comes in earlier.
TRX 363R 02- Laeger Narrow Frame/CR500 Link, Motowoz Suspension, Roll Design +4 LT Arms,RPM Dominator +4 axle, LED 363 MX, LED 350G Pipe, 38 A/S CR Ignition

TRX 363R 86- Stock frame(gusseted),KOQ-No Link Swinger, JD MGC LT Arms) Motowoz Shocks, LED 370/350D pipe, 38 A/S Carb, CR Ignition