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Eventually and ideally, i'd like to have all 3. From other posts here, I've learned that getting the carbs before the big bore kit is preferred. But what if new Cams for the 865cc engine is thrown into the mix. Which is the biggest bang for the buck?

FCR39 and the TPUSA cams are about the same price. The Wiseco 904 bore kit is a bit cheaper. Or should I just go straight to the HSR42? These mods probably won't be happening soon, but I want to plan/save appropriately. So, to sum it up, should I go:

1. Stock 865 with FCR39 (or Mikuni)
2. Stock 865 with TPUSA cams
3. Wiseco 904 with CVK36

Thanks!
 

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really, you're right, all 3!

I did it in this order: 904 kit, HSR carbs, and next I'm doing cams.

Try the carbs first. They give you more power all over but esp on top.

Cams will give you more on top.

Big bore (higher compression) will give you more torque and power everywhere.

All of the above will net you around 80-84 rear wheel hp and one fun fast twin.
 

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The HSRs use their own throttle assembly (and cables) and all parts are included in the kit.

They are pretty much a bolt on, and the kit is well thought out and they will come pre-jetted as close as can be estimated to your setup.

The HSRs DO NOT use the TPS. The TPS is left disconnected, but it doesn't have any negative effects.
 

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I d be tempted to upgrade the suspension and the front brakes before doing any of the above. Especialy the front brakes, I took a 1050 Tiger for a ride made me realise how bad our front brakes are.
:eek:
 

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I'd go with the Wiseco 10.5:1 865 pistons to get the higher compression and put the money saved towards a cam and carbs. The 865's really can use a better cam.
Have done one of those yet? I want to see some dyno runs on them.
 

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Wiseco recommend a light hone to break the glaze and the bore is ready to go. Nikosil is so bloody hard it takes 10 of thousands of miles for any wear to show. Should be fine on any bore that's done less than 30-40K. I'll let you know in a month or so with before and after dynos.
 

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I dont think wear would be a factor but how much the jug has moved around is another factor .If its still round and true.Regular hone stones wont work on the coating Ithink you need some high $ stones for it and the coating is not that thick,so you couldnt take much out to get it right.I think I might try a set on my spare motor I have a set of 865 jugs that are like new.The best test would be to put them in a motor with a good head ,cams ,pipes and carbs .Then dyno it .Then make it a 904 with the same head and other parts.
 
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