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So Ive decided its time to pull apart my favorite machine and freshen it up, and I'm looking to make some improvements in the process. I already have a 3x3 mod and a JD jet kit done and it seemed to have changed the world. The stock bike just plain sucked and now its a lot better. I never expect 450 race bike power here but I know there is a little more and I'm wondering if the juice is worth the squeeze. I already plan to add a header and exhaust, an FCR39 carb and stage 1 hotcams. After some research it really seems like those places are where the gains actually come from, so would it be worth it to throw a 434 big bore kit at this bike or just stick with what I already mentioned and a new stock bore top end??? Also my rides are often solo and pretty isolated,2014783812_ScreenShot2018-10-06at4_17_20PM.png.68182de0563dee3a479e2ef127a9efeb.pnghow much of a reliability headache can I expect with these mods? 

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So Ive decided its time to pull apart my favorite machine and freshen it up, and I'm looking to make some improvements in the process. I already have a 3x3 mod and a JD jet kit done and it seemed to have changed the world. The stock bike just plain sucked and now its a lot better. I never expect 450 race bike power here but I know there is a little more and I'm wondering if the juice is worth the squeeze. I already plan to add a header and exhaust, an FCR39 carb and stage 1 hotcams. After some research it really seems like those places are where the gains actually come from, so would it be worth it to throw a 434 big bore kit at this bike or just stick with what I already mentioned and a new stock bore top end??? Also my rides are often solo and pretty isolated,2014783812_ScreenShot2018-10-06at4_17_20PM.png.68182de0563dee3a479e2ef127a9efeb.pnghow much of a reliability headache can I expect with these mods? 

What brand kits are you considering?

 

Why do you want more power?

 

You have a nice setup for overlanding.

 

Ever consider ACT gears? A big bore kit is said to compliment them well, and lower rpms mean a longer life for the big bore.

 

FCR, Hot Cams, and full pipe will really wake it up. Maybe start there first before cracking it open?

 

 

Edit: I would go with Stage 2 hot cams or some used E cams. They are almost identical if I remember correctly.

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I was thinking about the ACT, which might solve my current issue actually... I went to 15/42 gears to bring my highway revs down because I have to crunch a lot of miles to get to where I want to go. But with 15/42 it has the potential to stall in tight spots and doesn't have a lot of low punch. I guess with act gears I could run 15/44 and still keep low highway revs. Wouldn't save me any money but I guess at this point I've gone so far I might as well go all in. Ive been looking at the Athena kit and the Cylinder works kit. I think FCR, Cams and Exhaust with 15/42 would probably accomplish my goals but I need a top anyway as it seems to be drinking more oil these days, about $200 for a stock bore rebuild or $525 for a BB kit. 

I probably could throw cams, carb and exhaust at it and see what it does before I do the top end and then decide which one I need. I'm just worried more CC's = More problems

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I was thinking about the ACT, which might solve my current issue actually... I went to 15/42 gears to bring my highway revs down because I have to crunch a lot of miles to get to where I want to go. But with 15/42 it has the potential to stall in tight spots and doesn't have a lot of low punch. I guess with act gears I could run 15/44 and still keep low highway revs. Wouldn't save me any money but I guess at this point I've gone so far I might as well go all in. Ive been looking at the Athena kit and the Cylinder works kit. I think FCR, Cams and Exhaust with 15/42 would probably accomplish my goals but I need a top anyway as it seems to be drinking more oil these days, about $200 for a stock bore rebuild or $525 for a BB kit. 
I probably could throw cams, carb and exhaust at it and see what it does before I do the top end and then decide which one I need. I'm just worried more CC's = More problems


(Hoping Erik will chime in)

You are definitely geared REALLY high.God bless that poor clutch. Ooooof!

I am going to try 15/47 with the ACT gears before I make a final gearing decision. But even 14/47 looks far more acceptable with ACT gears.

Oil consumption is a good excuse for a new jug and piston. You can always do a compression/leak down test?

Bbk with the other mods plus the ACT gears would make for a stellar setup on long trips to the trails.

I would reccomend getting a junk motor and just swapping them after you build the new setup.

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I was just reading Eriks post on compression tests, I think Ill start there. You really think 15/42 is that rough on my clutch? I figured it oughta be safe since the sm uses 15/41. I used that online gearing calculator and at highway speeds I can't remember exact numbers but I think it dropped me close to 500 Rpms at 70 in 5th. 

I agree if I'm going that far it would probably be easier to buy a second motor and then when it takes me a month to finish I can still ride. But now we're talking another thousand... any idea where to hunt one of those down ?? 

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They can be found complete for under $200

 

Also the SM does use that gearing, but the wheels/tires are smaller so the final drive ratio would be higher with your dirt wheels.

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7 minutes ago, revelc said:

Also the SM does use that gearing, but the wheels/tires are smaller so the final drive ratio would be higher with your dirt wheels.

I didn't really think about that at all to be honest. Good thing I only put 300 miles on it like that. 200 is a price Im willing to pay to be able to ride while I build my new Motor. 

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I have 14/45 gears on my ACT setup with SM wheels and 1st is nice and low but still don't shift to 5 till 55-60mph , I have a 47t for my rear winter wheel. 15/47 would be a little higher and a big bore definately needed at min.  You'd be best with 14/47 and it'll still be much lower rpm for 70-75mph. The ACT spacing really spreads the gears out , a little too much personally but works , just requires power . Wish the Nova gears weren't so ridiculously priced , I'd recommend them mostly . The lower final gearing makes the spacing less a gap feeling as well .

I used 15/40 on my stock motor when I had it in the bike , as long as your not dragging the clutch it's fine , only when offroad and you need to constantly feather it for hour on end does it become hard on it . Was quite a pooch taking off .

.

Edited by jjktmrider
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42 minutes ago, jjktmrider said:

I have 14/45 gears on my ACT setup with SM wheels and 1st is nice and low but still don't shift to 5 till 55-60mph , I have a 47t for my rear winter wheel. 15/47 would be a little higher and a big bore definately needed at min.  You'd be best with 14/47 and it'll still be much lower rpm for 70-75mph. The ACT spacing really spreads the gears out , a little too much personally but works , just requires power . Wish the Nova gears weren't so ridiculously priced , I'd recommend them mostly . The lower final gearing makes the spacing less a gap feeling as well .

I used 15/40 on my stock motor when I had it in the bike , as long as your not dragging the clutch it's fine , only when offroad and you need to constantly feather it for hour on end does it become hard on it . Was quite a pooch taking off .

.

So do you think with 14/47, ACT and cam, carb, and exhaust I'd still be wanting the big bore kit after a while ?

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So do you think with 14/47, ACT and cam, carb, and exhaust I'd still be wanting the big bore kit after a while ?
You can install a stroker crank while you have the engine open for the tranny cogs.

That would give a little more grunt to compensate for the power loss of taller transmission gears and you can add a big bore kit down the road if you still want more power.
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If your travels swing thru drastic altitude changes, consider a CVK40.

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1 hour ago, Zach7018 said:

So do you think with 14/47, ACT and cam, carb, and exhaust I'd still be wanting the big bore kit after a while ?

Pretty much doing the ACT gears the big bore is highly recommended at minimum , don't think it pays to use the stock bore as long as the whole thing is apart . Stroker adds more and is that much nicer but not a must and is probably a little better for down the road . Going with a higher comp setup(12:1) gets you the lower end oomh needed to not have to rev high between each gear change .

 

.

Edited by jjktmrider
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14 hours ago, 38super said:

If your travels swing thru drastic altitude changes, consider a CVK40.

On my last trip, my altitude varied from -231ft up to 4200ft, and often I find myself going higher than that. I am moving soon so that might not be the case anymore but I have heard that the stock S carb does better with elevation changes than the FCR39, can you or anyone elaborate on why that is and what the improvement is with the CVK40? 

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Oooo, DV.  CVK is just a bigger BSR, constant velocity (CV) carbs are less sensitive to altitude changes.  FCR is a streetable race carb, tad more sensitive.

Doesn't mean an FCR won't work.  Expect an FCR is bit more jetting fussy. 

I've ridden from South Bay to Wrightwood, jetting was very rich at Krakta Ridge / Mt. Waterman.

 

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4 minutes ago, 38super said:

Oooo, DV.  CVK is just a bigger BSR, constant velocity (CV) carbs are less sensitive to altitude changes.  FCR is a streetable race carb, tad more sensitive.

Doesn't mean an FCR won't work.  Expect an FCR is bit more jetting fussy. 

I've ridden from South Bay to Wrightwood, jetting was very rich at Krakta Ridge / Mt. Waterman.

 

Doing some reading on it I think you just saved me a couple hundred. Seems like the CVK40 is pretty comparable to the fcr, way more available and a lot cheaper. It doesn't seem like the fcr would be a major issue but riding in Southern California as you the elevation change is just insane if you go anywhere worth going so I would rather not deal with a fussy carb. Thanks for steering me in that direction!!

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ADV riding means bullet proof.   Just to add, take a look at this LA B to V vid.  Paul Flanders (D37) is the guy being interviewed at AV KTM.  Mind his words on spares and what to bring, I'd rather preach to the choir than to hear of a lost rider.

https://www.youtube.com/watch?v=9ZWUPvr3E7A

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So Ive decided its time to pull apart my favorite machine and freshen it up, and I'm looking to make some improvements in the process. I already have a 3x3 mod and a JD jet kit done and it seemed to have changed the world. The stock bike just plain sucked and now its a lot better. I never expect 450 race bike power here but I know there is a little more and I'm wondering if the juice is worth the squeeze. I already plan to add a header and exhaust, an FCR39 carb and stage 1 hotcams. After some research it really seems like those places are where the gains actually come from, so would it be worth it to throw a 434 big bore kit at this bike or just stick with what I already mentioned and a new stock bore top end??? Also my rides are often solo and pretty isolated,2014783812_ScreenShot2018-10-06at4_17_20PM.png.68182de0563dee3a479e2ef127a9efeb.pnghow much of a reliability headache can I expect with these mods? 


I had the Cylinder Works BB kit, ACT gears, full FMF Q4 exhaust with JD Jetting and airbox mod done earlier this year on my S model. Hey, it is a new bike. Good power, still low enough gears for off road. And on the highway, 65 mph at 4,700 rpm and 70 at 5,100. Standard 15/44 factory sprockets. It truly is a light weight adventure bike now.
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I had the Cylinder Works BB kit, ACT gears, full FMF Q4 exhaust with JD Jetting and airbox mod done earlier this year on my S model. Hey, it is a new bike. Good power, still low enough gears for off road. And on the highway, 65 mph at 4,700 rpm and 70 at 5,100. Standard 15/44 factory sprockets. It truly is a light weight adventure bike now.


How do you like your Tusk panniers? What is you estimate for added weight of panniers and all your gear for an extended camping trip? Thanks.

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4 minutes ago, m-johnson said:

 


How do you like your Tusk panniers? What is you estimate for added weight of panniers and all your gear for an extended camping trip? Thanks.

 

In all honesty I have no clue about weight, I can tell you a few things,  I really like them, they're a good bang for the buck and everything I need them to be. If you do a lot of off-road and don't ride with motocross boots you will surely want to start because planting a foot for any reason can quickly result in a pannier smacking the back of your leg and without boots and I think there is a potential for injury there, (you can run soft bags easily if you're planning some real hard off-road). You have to fit the mounts to the boxes yourself, not too large of a task, and just a tiny bit of layout/fab knowledge and you can get them both level and in line with each other easily... and as for weight..... this is my first set of hard panniers so maybe in relation to others they're not bad, but I think they're a little heavy, I also carry A LOT of tools and gear(been stranded before so I pretty much pack a mechanic shop) and I'm also not making the horsepower that you are and I'm sure ten more ponies would change my opinion quite a bit.

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EveRide did a pretty good review on them

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