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Discussion Starter · #1 ·
ha senyone attempted to make single carb set up for 450 equal length mani? thinking of doing this .any down sides or atvantages to this?
reason i ask is ,i saw a manifold for an xs650 on ebay and got me thinking for my bobber project.
 

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Sensei
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On a 450 frame, the central downtube is in the way of "equal length" adaptations... On a 360 type frame, it could work fine....Remember however that a longer intake tract will help low end "grunt" but can hamper midrange and top end unless "more carburetion" is applied (bigger carb)... While a single carb can greatly simplify tuning, the "one carb per cylinder" models with shorter intakes tend to be quicker....
Examples: CA77 (305 Dream) vs CB77 (Superhawk)
Triumph Thunderbird vs Bonneville
Honda Rebel 250 vs Honda CB 175 ( both have ~18 HP but the twin carb 175 is quicker, even with signifigantly less displacement, and top speeds are nominally the same......
We used to go the opposite direction and insert 1/2" thick "torque plates" under the carbs on our dirt bikes (to get a longer intake tract)....
 

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Discussion Starter · #4 ·
thanks guys ill keep that in mind ,not really into speed, just cruising around at 35mph dont intend to hit the highway or long trips . so low end should be just right, no?
 

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Sensei
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If you will primarily be riding at 45/50 or below, the 450 is WAY overkill...
I ride the same way...That's why I'm building a CL175...... (a Rebel (250) or Twinstar (185 or 200) already has the single carb set-up, although a vintage CD175 (Also single carb) would be way cooler..... JMHO...... :D ;) Steve
 

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Sensei
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Well now... On a $50 bike I might try altering the frame to remove the offending center rear downtube, and replace it with some triangulated side rails..... Then your equal length manifold is a possibility... However, if your compression is good and the 450 engine runs well, you don't need any more initial torque....lol.... Steve
 

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Discussion Starter · #8 ·
just a question regarding tires, am i able to put a 120/90/18 in the rear or would there be a problem with the chain rubbing the tire i know it,s off topic but didn't want to start a whole other thread.
 

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Sensei
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It'll be really close... You be adjusting the chain before each ride...JMHO....
 
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