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Looked all over the web for recent Webcam installs and best I could find is 2010. Looking to see if this is an actual upgrade for the motor or not really worth the cost. Any information would be helpful. Already un-corked the exhaust and opened the airbox flow flow. Just looking for going with a more power.
 

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I installed a MegaCycle camshaft. It is more expensive than the WebCam but I liked the profile better -- about the same lift but longer duration -- and everybody uses WebCams and I wanted to be different. (Costs about $100+ to be different.)

http://tw200forum.com/forum/performance-customization/37817-camshafts.html

For me, I think it was a positive addition. Notice I didn't say "worth it" because it ain't cheap. The camshaft I picked gave a slight loss of low end torque (which the TW has plenty to spare) but the upper end, especially above 8000 rpm seemed to wake up. It also took a little carb tuning and a rebuilt CDI. Incidentally, I am using the stock 14/50 sprockets.

If you decide to go with a new camshaft make sure you report back here your results -- good or bad. Other people will then be able to use the info for themselves.
 

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I am new here, but have been reading a lot here and elsewhere. The cam upgrade seems to be the best bang for the buck upgrade compared to exhaust, K&N, etc. I am leaning toward the WebCam due to cost and my general theory on valves is to open them bigger moreso than longer although elime´s theory of longer not higher could be right. Both the WebCam #40 grind and the MegaCycle can use the stock valve springs. Elime has the older carb and i have the newer carb (I bought a 2015 although I owned an ´87 and ´88 in the early 90´s) The only downside I see is that the motor will run hotter in the Summer with the cam breathing better and making more power. Would want to watch for any signs of heat issues. Also, I thinkk the MegaCycle requires new rocker arms and the WebCam does not. Another price differentator. It would be nice if someone would post a YouTube video on changing the cams. I am probably competent at this, but it would be nice to see a video on one the the few topics that there is no video for.
 

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The cam upgrade seems to be the best bang for the buck upgrade compared to exhaust, K&N, etc.
You might also consider a larger piston. A 70mm piston can be bought in China for about $30 or $40. A 70mm Wiseco high compression piston can be had for about triple that cost. Add in gaskets and a machinist to bore the cylinder and that is easy another C-note.

If you have been following Cornelus' engine build thread, he says he has had excellent results with the pumper carb from China. I bought one and it sits on a shelf in the garage but I think it was less than $30, maybe even closer to $20 than $30 -- I don't remember. Another option. It is NOT a bolt on. The intake manifold needs to be modified or fabricated. Also the cable is different and needs imagination to make it work.

I have the older carburetors. I like them because I can get high speed and pilot jets from China for $10 per dozen and I bought 2 dozen of each. They let you pick the sizes you want so I had quite an assortment both richer and leaner than stock, multiple examples of each size. I had so many extra ones I was passing them out however the supply has dwindled to the point I only have enough for me now.

I used new rocker arms with my MegaCycle camshaft. I bet a lot of them get installed with used rocker arms. I found a cheap set of new ones on ebay, rocker arm shafts too, by plugging the part number into the search thing and I got lucky. Give it a try. I actually bought 2 sets because I have 2 TW's and thought someday I may want a new camshaft in the other one. The used rocker arms looked so good if I hadn't already bought the new ones I would have used the old ones and not worried one iota about it.

Good luck and keep us informed of your progress and results.
 

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Thank you for your well-considered response. The cam and the high compression piston (I have looked at the Wiseco stock bore high compression piston) both increase the heat. Both together would probably lead to reliability issues in the Summer. Also, the piston requires the use of premium gas. Premium gas is at least 50 cents more here and while not a big concern for a bike that gets over 65 mpg, I hate to pay the premium tax. Also, reading the performance increases of both upgrades, the cam seems to be at least as good and doesn´t require premium gas. Even with premium the high compression piston is more likely to knock in lugging situations. Overall, I think the high compression piston would add more heat. Also, I am not interestred in boring an almost new engine (1600 miles) and all that expense, when I can just pop a cam in and go. The hgh compression piston would probably actiually increase mileage slightly while the cam would probably either not impact it or very slightly lower it.

I had an 87 and 88 in the early 90´s and my memory was that those non-cv carbs were more responsive (maybe they didn´t have to tune them so lean). Anyway, I have ordered the 128 and 130 jets and the 34 pilot jet for my CV carb. I also have shims from previous carb escapades. I already took the initiative to drill out the cap on the pilot screw and turn it out to over 2.5 turns and the bike runs much better (it was redicullously cold natured before). There is stiil a slight hesitation when you crack it open from low speed. Needle probably needs shimmed for sure. Also have K&N air filter on the way.

From what I have read, the 128 jet is a waste and the best setup for my carb is 130, 2 or 3 shims on the needle and the 34 pilot jet around 1.75 turns out. I am probably staying with the stock exhaust and taking the spark arrester out when I want more power. That way I can have relatively quiet and more power when needed. Plan to tune with both to get best overall setup. Realize I will be a little lean without spark arrester and rich with. I already made a tool to adjust pilot screw so might have 2 settings for pilot screw depending on spark arrester. This might work well since pilot jet puts some fuel in at all speeds.

Great forum and I am hoping to get to my 10 post goal so that I can start a thread. Have a new idea for eliminating seat bolts.

The only thing that is stopping me from buying the cam tomorrow is that there is no video on cam replacement for the TW. I am fairly competent, but would like to see someone do it for reasurance that I don´t make a mistake or that there aren´t any ¨gotchas¨.
 

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I can see your point about a new, low mileage bike and you don't want to tear into it. The only compromise I can think of would be to get a dirty, rusty, cylinder for cheap off ebay and bore it out for the new piston and keep the original cylinder and piston on the shelf so the bike can be put back to stock if so desired.

As for over heating, I personally never give it a thought and have never had a problem with it. I have seen over heated pistons so I know the problem exists but for me it just hasn't happened, at least not yet. I once rode my TW across the San Joaquin Valley during a heat wave holding it near wide open throttle. My buddy said the electric fan on his water cooled bike kept coming on but my TW never hiccuped or burped.

As for premium gas, I use it all the time anyway. I know, probably a waste of money but it makes me feel better. I know some other that have installed Wiseco high compression piston and have been cornered where their only choice was regular gas and they reported it worked OK. Stock compression is 9.5:1 and the Wiseco is 10.25:1, not really huge increase.

I have to start over tuning the carburetor on my modified TW. I was trying to tune out a miss after I installed the new cam and the miss ended up being a bad CDI. I don't know if the miss was there before the cam swap as it was very minor and only became an annoyance with the new camshaft.
 

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Yeow! those seem to be minuscule improvements for the cost on this engine. Mine is rejetted properly and practically never needs choke. Except for extreme cold. My personal best upgrades would be the fork solution kit, rear spring upgrade, a real skid plate, and man sized handle bars and foot pegs, all available from Pro-Cycle. your looking at around &700 us for all that but your not going to get that much more grunt out of 200 cc's at any cost.
 

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Yeow! those seem to be minuscule improvements for the cost on this engine. Mine is rejetted properly and practically never needs choke. Except for extreme cold. My personal best upgrades would be the fork solution kit, rear spring upgrade, a real skid plate, and man sized handle bars and foot pegs, all available from Pro-Cycle. your looking at around &700 us for all that but your not going to get that much more grunt out of 200 cc's at any cost.
What size jets did you use Pete?
 

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I have no idea what jet is in mine. The old guy I bought it from last summer told me when he bought it in 09, the shop mechanic mentioned to him that he "fixed the lean condition". Like I said, mine almost never needs choke, and the plug is a perfect light brown. I'm at about 800 ft above sea level here in upstate NY. Right now it's cold here and my shed is not heated, but I'd still be glad to dig into it to find out if it's not too much trouble, and it would be helpful to others. I'm in my 50's and have been riding since the mid 70's. My other machines all have FI but I'm not unfamiliar with Mikuni carbs although I've never done much more than chance the c-clip level on the slide needle on other bikes I've owned. You guys would have to let me know exactly what I'm looking for and where to look for it.
 
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